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MIDWEST USA SEDIMENTARY TYPE GEODES

Posted by Bob Harman  
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Bob Harman February 25, 2012 07:32PM
As there is a large subgroup of US mineral collectors that specialize in USA Midwest sedimentary type geodes and many more casual geode collectors out there, I am starting a new topic devoted to pix and accompanying short descriptions of these specimens, either self-collected, traded, or bought. I hope the posts will be only of this type geode.....no foreign geodes of any type and no igneous Western or Northeastern geodes and also no concretions or nodules; just Midwest geodes as from the Keokuk area, Missouri and Illinois, Indiana and Kentucky including the Hall's Gap area. If you have any nice pix and stories on this topic, please feel free to post them on this thread. These 3 examples are from my collection of Indiana geodes. Aragonite on quartz with ferroan dolomite from Monroe county, Smoky quartz on white chalcedony from Monroe county and millerite with calcite on gray-blue chalcedony from Monroe county. BOB HARMAN
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Stephen Rose February 25, 2012 10:37PM
Good idea, Bob. And, you got it started before my scheduled break from work on taxes!

One thing that I would like to see; whenever you have specimens that should be represented on the Mindat locality/picture data base, lets get them in there. There are a couple that you just posted that are unlike anything currently shown. In addition, locality pictures are often lacking and are just as important as the specimen pictures to folks unable to actually visit the locations. What do you think?



Geode with dolomite, baryte and quartz, SR 37, .5 miles north of Harrodsberg, (cut #18) Monroe County, Indiana. 6x5x8 cm. Circa 1965. The baryte in this geode shows signs of solution damage and crazing while the dolomite is pristine.

Cheers!

Steve
open | download - INBaryteDolomiteHarrodsberg.jpg (577.4 KB)
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Byron Thomas February 25, 2012 11:48PM
I like this topic, i will be adding to this very soon. Its all a matter of me taking some better photos.


Indiana born and raised and still living there




Byron
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Bob Harman February 26, 2012 01:29AM
Three more Indiana geodes from my collection. The first is a 15 x 8 cm geode with a stout 5 x 3 x 1.1 cm color zoned barite from Monroe county, found in the 1980s. The second is a very unusual geode. It is oval, about 15 x 8 cm and shows crystalized quartz on gray-blue microcrystalline quartz (chalcedony). I have the whole geode and it is probably a geodized fossil. Self collected from Monroe county, found in 2007. The third pix is from Washington county and is a self collected geode about 12cm with 2 pristine calcites, the larger of which is about 5 cm. Hope to see others post their pix, especially of sites in other Midwest states! BOB
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Kenneth Vaisvil February 26, 2012 01:50PM
Are those quartz or calcite crystals on the blue chalcedony geode section? -- Very impressive geodes ! - thanks for sharing
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Bob Harman February 26, 2012 03:30PM
As barite in Indiana geodes is so highly sought after, I collated several pix from other threads together onto this theme. The first pix is of a parallel group of blades with central yellow color and tips of a pale blue-white color. Click the pix to hone in on the barite group and note, near the top center of the barite, the millerite strands from the quartz thru the barite into the geode cavity. Monroe county, March 2011. The second pix is a 3.3 pristine grouping of delicate crystals. The largest is 2.5 cm and double terminated. Monroe county, about 2000. The third pix is of a 5.5 cm stout blade nestled in the "back" of the 10 cm geode. Monroe county, March 2010. Many, many Indiana geode barites have been found. The trick, of course just as with all mineral specimens, is to find large and/or pristine crystals, perfect or nearly so in every way...................... Hi Ken! hope you get some of your great specimens onto this theme. Yes, those are quartz crystals and not calcites. Click on the pix to hone in and enlarge the pix. The geode is an amazing very large variant of the dewdrop diamond variety. ENJOY, BOB
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Kevin Conroy February 26, 2012 07:21PM
There are quite a few older geode producing areas in the Midwest that some collectors may not be aware of. I just uploaded a few pics of specimens from Missouri, one a road intersection in St Louis County, the other an old iron mine not far from Rolla. You can see them here: http://www.mindat.org/xpic.php?fname=0090990001330278356.jpg
http://www.mindat.org/photo-447932.html
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Stephen Rose February 26, 2012 07:56PM
Kevin Conroy (2) Wrote:
-------------------------------------------------------
> There are quite a few older geode producing areas
> in the Midwest that some collectors may not be
> aware of. I just uploaded a few pics of
> specimens from Missouri, one a road intersection
> in St Louis County, the other an old iron mine not
> far from Rolla. You can see them here:
> http://www.mindat.org/xpic.php?fname=0090990001330
> 278356.jpg
> http://www.mindat.org/photo-447932.html

Kevin, great picture and an unusual locality. In about 1965 I used to do some business with a dealer named Bill Banks; he would stop in Bloomington to peddle his specimens. I had some very nice millerite at the time but he said that he wasn't interested because he could get much better from St Louis. I never knew what he was comparing mine to. Maybe it was something like the one you referenced.

Thanks for sharing!

Cheers,

Steve
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Stephen Rose February 27, 2012 07:48PM
I have always liked these pseudomorphs after millerite but have never pinned down what they are exactly. Something in the jamborite-honessite realm, I suppose. The orange color is quite distinctive and does not seem to fit well for either of those two species. If anyone has information about them I would like to hear from them.

These are from the "aragonite" road cut, (old) SR37, 5.25 miles north of Bloomington, Monroe County, Indiana. Both specimens were collected in 1966.

The first is a small geode with calcite enclosing the orange mineral pseudomorph after millerite. 4x3.5x2 cm.


The second is a calcite cleavage from a geode enclosing a spray of the same orange mineral. 4x3x1.2 cm.


Cheers,

Steve



Edited 2 time(s). Last edit at 02/27/2012 08:16PM by Stephen Rose.
open | download - INGeodePseudo1.jpg (945.4 KB)
open | download - INGeodePseudo2.jpg (985.8 KB)
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Kevin Conroy February 27, 2012 09:25PM
Hi Steve,

Thank you! There are (were) several places near St Louis that produced good millerite specimens, but not necessarily in geodes. Unfortunately now almost all of these are gone. There are a few small areas left, but they don't produce anything like they used to.

I think the best place for millerite in Missouri was the Leadwod roadcut. There were some pretty decent specimens found during construction. I looked and saw that there aren't any photos posted yet, so I just took two from my collection. The spray in the first photo is about 2.5 cm, the second is about 3 cm.



As for your yellow/orange pseudos, they may be honessite. Check out the photos here: http://www.mineralatlas.com/specials/pseudo3.htm

All the best,
Kevin
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Kenneth Vaisvil February 28, 2012 04:21AM
My favorite geodes are the Keokuk area geodes. They have a fantastic variety of calcite crystal habits inside them. Here are three I collected. The pagoda style clear over pink scalenohedral calcite is from Lewis County, Missouri near Canton, the iridescent pseudocubic crystal is from Brown County, Illinois and the 2 cm barrel calcite is from Hancock County, Illinois near Pontoosuc.



Edited 1 time(s). Last edit at 02/28/2012 04:31AM by Kenneth Vaisvil.
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Kenneth Vaisvil February 28, 2012 04:43AM
Here are two iridescent calcite geodes - my favorite types from Brown County, Illinois.
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Rick Dalrymple February 28, 2012 05:54AM
Kevin,

Great link. I found a small error. On page 9 it shows a "Martite (black iron rich sphalerite) pseudomorph after magnetite". Martite is not an iron rich sphalerite, but simply hematite pseudomorphed after magnetite.

Ironically, the photo showed on the link is the same one as the featured specimen on the martite page here on mindat, with the correct info.

Rick
I know I am in my own little world, but everyone knows me here.
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Bob Harman February 28, 2012 03:54PM
Aragonite, a crystal polymorph of calcite, is occasionally found in Indiana geodes, but not nearly so commonly as calcite. The best known aragonite location is the road cut North of Bloomington in Monroe County, on Indiana route 37. This was heavily collected for many years and the subject of an article by mindat contributor Stephen Rose et. al. in Rocks and Minerals 1966 - 1967. Many other small and very localized areas of aragonite geodes occur in Monroe and neighboring Lawrence counties. These geodes are often found in heavily fossilized sandy siltstone type formations. These geodes are often accompanied by decomposing ferroan dolomite going into ankerite (old limonite terminology). The first pix is of a 12 cm geode showing sprays of aragonite and quartz coated by aragonite; it was found in July of 2011. Pictures 2 and 3 are both halves of the same 13 cm x 9 cm geode. Found in 2007, it shows sprays of aragonite on quartz. It is unusual in that no other aragonite coats the quartz crystals and virtually no ferroan dolomite is present.



Edited 1 time(s). Last edit at 03/05/2012 10:45PM by BOB HARMAN.
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Harold (Hal) Prior February 28, 2012 04:47PM
One of the best Millerites from any locale has to be the superb Missouri Millerite (Glenn Williams collection specimen) that was featured on the cover of the Missouri Issue of Rocks and Minerals Magazine. They don't get much better than that! a quarry in the Troy, Missouri area produced some excellent millerite altering to green honesite in calcite during the 1960's.
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Bob Harman March 02, 2012 08:29PM
Calcite, along with dolomite are probably the 2 most common collectible secondary minerals found in Indiana quartz geodes. Calcite takes on many differing appearances within geodes; rhombohedral crystal forms and variations on this are more common than scalenohedral crystal forms. The first pix shows a 4 cm complex rhombohedral xtal in a 9 cm geode from 2004, Monroe county. The second pix shows a very unusual pinkish double terminated 3.1 cm rhombohedral xtal on blue chalcedony in a 8 cm geode. This appearance is similar to those crystals found in geodes from Western Illinois and Missouri. The third pix shows a complex grouping of orangish rhombohedral crystals largely filling the cavity of a 9 cm gray-blue chalcedony geode. Monroe County Indiana............ Hope others collecting Midwest geodes submit some of their specimens onto this theme for all to see. BOB
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Stephen Rose March 03, 2012 08:51PM
Kenneth, that Brown County pseudo cubic calcite/calcite is really unusual.

This is a millerite that I posted on another thread a couple of years ago. Weakly attached mass of radiating tufts of brassy crystals in a chalcedony geode. Hoopston, Vermilion County, Illinois. Larger 'half' is 6x6.5 cm. Circa 1960. Acquired by exchange with M. Papcum in 1967.



Cheers!

Steve
open | download - ILHoopstonMillerite.jpg (633.5 KB)
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Everett Harrington March 05, 2012 05:44PM
Hi Gang, going to add a few of my pieces to this thread....Note all of geodes and crystals are from Harrodsburg Indiana area. First is a geode with dolomite and calcite, what is unusual about this geode is the main calcite was broken and rehealed in place by just a small amount of calcite http://photos.imageevent.com/everett_harrington/indianatripmay07/large/100_3688.jpg

Next is a couple of clacites that were loose in a volley ball sized geode that I found that had fallen around 20 feet to the road. everything was loose in this geode so I only ended up with single crystals. Calcite and baryte on the right
http://photos.imageevent.com/everett_harrington/harrodsburhnov05/websize/Picture%20005.jpg

Loose barytes from same geode some were double term!!
http://photos.imageevent.com/everett_harrington/harrodsburhnov05/websize/Picture%20009.jpg

Next we have a calcite that had a weird term because of a baryte blade that truncated the growth
http://photos.imageevent.com/everett_harrington/harrodsburhnov05/websize/Picture%20021.jpg

And last, a huge sphalerite that was etched out of a solid calcite geode
http://photos.imageevent.com/everett_harrington/harrodsburhnov05/websize/Picture%20010.jpg

enjoy!
E



Edited 2 time(s). Last edit at 03/05/2012 05:50PM by Everett Harrington.
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Everett Harrington March 05, 2012 06:10PM
More to come later :)
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Byron Thomas March 05, 2012 07:09PM
I was hoping you would get into this Everett. Now if i could figure out how to get my camera to take small photos i could add to this geode fest.
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Everett Harrington March 06, 2012 04:00AM
Yeah Bob and I talked at the FOM meeting in Richmond this weekend...told him I'd add a photo or two :)


Byron what you doing April 14 and 15? want to collect some fluorite???

:)
E
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Everett Harrington March 06, 2012 04:32AM
Next are some Kentucky geodes from the Sommerset area.

Fossil replacement of Brachiopod

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20063.jpg

An average quartz geode, but something special about it....all of the quartz crystals are bipyramidal!

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20081.jpg

Close up of above

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20082.jpg

Some nice sized dolomite crystals

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20043.jpg

Calcite and aragonite with unknown pink material

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20050.jpg

Dolomite calcite and unknown pink sponge like mineral?

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20060.jpg

Close up of unknown

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20064.jpg

Quartz geode with slight amethyst spot lower left

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20071.jpg

Larger geode with celestine

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20072.jpg

Close up of above

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20073.jpg

And sometimes the bipyramidal quartz crystals do sometimg fun!!!

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20036.jpg

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20037.jpg

http://photos.imageevent.com/everett_harrington/kydec2007/websize/k%20038.jpg

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20078.jpg

Close up of above

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20079.jpg

Of course they can be funny too....

"Running Buns"

http://photos.imageevent.com/everett_harrington/inkynctripjune2008/large/NC2008%20072.jpg

Enjoy!!
E
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Bob Harman March 06, 2012 04:44AM
The first pix is part of my 2011 exhibit at the Cincinnati show. This case had several very large Indiana geodes. All were self-collected or acquired over the past 8-10 years. The depicted geodes have calcites, barites and aragonite as secondary minerals. The 2nd pix is a closeup of one of the geodes with 2 large calcite rhombs and some adjacent barites. The geodes in this case were all unusually large to be this fresh and displayable......"big is beautiful". Enjoy BOB
open | download - 2011Cincinnatirockshow 004.jpg (972.9 KB)
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Everett Harrington March 06, 2012 05:11AM
Bob did you get my email??

thanks
E
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Byron Thomas March 06, 2012 06:49AM
Id Love to collect some Fluorite Everett, It all of course depends on my work schedule.
Keep me informed.

Byron
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Bob Harman March 06, 2012 10:29AM
EVERETT I did and I replied that all is a go for this weekend. Did you get my reply, as it had my phone #s ???? BOB
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Everett Harrington March 06, 2012 05:32PM
Hi Bob,
Sounds good, thanks for the email reply. Looking forward to some 3 inch barytes :)

thanks!!!
E
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Stephen C. Blyskal March 07, 2012 12:14AM
I have three geodes of this type that I got from the Fred Powers collection without any labels or information on where they were from. Can you tell me anything more about this location. Searching on Mindat for Brown Co, IL doesn't produce anything. I'll be happy to photograph them and post in this thread. Calcite on calcite geodes. Thanks
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Byron Thomas March 07, 2012 12:43AM
Stephen,

It should be Brown Co, Indiana more then likely.

Hey Everett where you heading to get Barites?


Byron
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Bob Harman March 07, 2012 09:30AM
Brown County ILLINOIS produces geodes that are distinctly different than Brown County INDIANA. You need to put a couple of good quality pix on this site to help make the id. Calcite on calcite sounds more like a Western Illinois geode as Brown County Indiana geodes tend to have micro minerals, such as goethite, on quartz. BOB



Edited 1 time(s). Last edit at 03/07/2012 09:35AM by BOB HARMAN.
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Stephen C. Blyskal March 07, 2012 04:29PM
Bob, Thanks for the info. I know they aren't Indiana. I did my geology grad studies at IU and knew all the collectors at the geology dept. Never saw any calcite geodes until I lived in St. Louis in the 70's. The collection I bought was from a man who had lived in St. Louis for many years and had mostly Midwest specimens. So I figured these unlabeled calcite on calcite geodes were from the MO, IL, IA area, but I didn't have a specific locality. I'll take some quick pics this weekend and post them here. I also have a number of other interesting Midwest geodes from collecting and trading over the years, including a large number from the Jim Maple self-collected collection. He grew up in North Vernon, IN and collected all over IN for years while getting his PhD at Purdue. I'll post as I have time.
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Everett Harrington March 07, 2012 04:49PM
One of the only spots I know of that have all calcite geodes is Geode Glen in Warsaw IL, it is the type locale for the formation the geodes are found in. It is down behind a baseball diamond in Warsaw......are the calcites very clear? any pyrite on them??

Byron, a couple of us are heading down to Bloomington/Harrodsburg this weekend for some geode collecting, we'll be hitting a few locations down there, right Bob :)

thanks
E
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Kenneth Vaisvil March 07, 2012 08:00PM
Steve,

I am very familiar with many Keokuk and St. Louis geode locations (many of which are not known to mindat) so I will give you my opinion on the photos you post as well.

Thanks,
Ken
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Bob Harman March 09, 2012 03:23PM
Dew Drop Diamond geodes occur in several Midwest locations including Indiana, but are rare and much revered by all Midwest geode collectors. The name was coined sometime prior to Steve Sinotte using it in his 1960 book on The Fabulous Keokuk Geodes. These geodes have dipyramidal quartz crystals.....often smoky...... sprinkled on white to pale blue gray chalcedony (microcrystalline quartz). So they are quartz on quartz geodes. Holding these geodes and moving them back and forth in the sunlight makes the crystals sparkle like dew in the early morning sun, hence their name. This 8 cm x 7 cm example, found in 2002 in Monroe County, Indiana, clearly is a geodized brachiopod fossil. It was difficult to adequately photograph and looks much better in person in the sunlight. Enjoy, BOB
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Everett Harrington March 12, 2012 04:01PM
Well, I've had a chance to look over Bob Harman's collection of IN geodes, it is by far one of the TOP 3 geode collections in the world. I was amazed at the gemmy barytes (some of which are a rival in themselves to top Meikle mine barytes!!), aragonites and other included minerals he has found over the years. One thing I noticed is that the photos on here do no justice to what he has. You would be hard pressed to find geodes from anywhere in the US to compete with Indiana geodes that Bob has amassed. Please show us your best finds of geodes, I'd love to see some from the Keokuk area that would rival what has been collected in Indiana.....Cudos Bob!! Thanks for the showing of your awesome collection!!

E
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Kenneth Vaisvil March 16, 2012 01:38PM
Yes, I have seen Bob's collection as well - and yes it is fantastic.
Indiana geodes definitely beat out Keokuk geodes with their barite crystals. But I think Keokuk geodes have better calcite and sphalerite crystals.
Attached are photos of my best two sphalerite geodes. The first is from Hancock County, Illinois and has a 1-1/2" tall pagoda calcite in front of a 2+" sphalerite group. The second is from Brown County, Illinois and has a 1" sphalerite group with aligned chalcopyrite crystals on it.
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Kenneth Vaisvil March 16, 2012 01:40PM
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Everett Harrington March 16, 2012 02:49PM
Hey Kenneth,
Those last two from Geode Glen? Look like the crystals I found down there :)

thanks
E
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Bob Harman March 16, 2012 06:26PM
Quartz geodes are extremely common thru out the Midwest, but finding really nice pristine display quality examples are not all that easy. These six examples are all from Indiana and show the wide variety of quartz, from microcrystalline quartz (blue chalcedony) to milky quartz, to smoky quartz, to clear and vaguely citrine colored crystals. The crystal size also varies considerably from tiny thru complex larger crystal terminations. While no true amethyst is found, occasionally vaguely amethystine colored crystals are found. The vast number of quartz geodes sold as "citrine" are not; they are just yellowish iron stained crystals.
Thanks to all the guys out there for their kind remarks regarding my collection! To be fair, there are other great collections of Indiana and Midwest geodes as well.....hope to see some additional pix from those collections as well. And what makes them so great is that many of the pictured examples would be SELF-COLLECTED!
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Rock Currier March 17, 2012 08:32AM
Bob,
Would you consider uploading your geode images to our general gallery? When they are left as attachments, they are hard to locate after a while and get buried in the mass of old messages. If you would like detailed instructions on how to do this see http://www.mindat.org/article.php/912/Uploading+specimen+images+to+Mindat

Rock Currier
Crystals not pistols.
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Stephen Rose March 20, 2012 01:33AM
This geode is from Harrodsburg, Monroe County Indiana, but is from the RT37 cut about a half mile north of town. 6x5.5x6.5 cm. Circa 1964.



Bright quartz with spheres of calcite of max 0.5 cm size.

Cheers!

Steve



Edited 1 time(s). Last edit at 03/20/2012 02:58AM by Stephen Rose.
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Byron Thomas March 20, 2012 06:15AM
WOW i have never seen spheres of Calcite in an Indiana geode, very very cool.
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Rock Currier March 20, 2012 09:16AM
A little removal of shadows in Photoshop make you image look like this.



Rock Currier
Crystals not pistols.
open | download - Calcite, Indiana.jpg (96.2 KB)
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Bob Harman March 20, 2012 12:57PM
Great and interesting pix Stephen! So, continuing on this theme of hemispheric carbonates in Indiana geodes, these pix show additional examples. The first and second pixs are of both crystalline (dissolution) calcites and numerous hemispheric calcites to 0.6 cm in an 18 cm geode. There is also some minor barite. Found 2006 from Monroe county. The third picture is 2 examples of hemispheric aragonites in 2 different 8 cm geodes from Monroe county, found in 2004 and 2005.
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Stephen Rose March 20, 2012 03:05PM
Rock, it's magic!

Byron, Bob has shown some great examples of the calcite "spheres." I recall that there were good examples at the R37N (aragonite) location in Monroe County that were not very uncommon. Snow white perched on dark ankerite in some cases.

Cheers!

Steve
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Everett Harrington March 20, 2012 03:45PM
Hi Guys,
So the white ball shaped crystals from the aragonite road cut are aragonite or calcite? Seems we found three like that, very neat pieces. The structure reminds me of prenhite!!


thanks
E
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Bob Harman March 20, 2012 04:10PM
Yes Dorothy, there are copper minerals in Indiana geodes!! Here are 3 examples of MALACHITE in Indiana geodes. The first is a hemispheric malachite microcrystal (?) to about 3 mm with nearby hemispheric calcites to 7 mm in size. Monroe county 2004. The second pix is of malachite on a grouping of hemispheric aragonites (yes aragonite!!). The whole grouping is about 1 cm, from Monroe county 2005. The last pix is of a 3mm malachite crystal with nearby aragonite coating quartz. Also, Monroe county, 2005. The question of aragonite vs calcite hemispheres has intrigued me over the years as I have many examples of both. Showing some of "each type" to several identification experts seems to confirm that in aragonite locales, the hemispheres are different and probably truly aragonite while other locales seem to have true calcite hemispheres. Incidentally, I also have chalcopyrite microcrystals and some are altering to malachite in several Indiana geodes. All these examples are from one aragonite locale in Monroe county. Go figure........, but enjoy! BOB
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Stephen Rose March 20, 2012 04:19PM
Everett,

Good question. I don't think that we ever tested these specifically but assumed calcite. To me they seem like they could be a form of the worm-like aggregates of calcite that are composed of very thin rhombs stacked on the C axis. These are late in the paragenesis and post-date or overlap aragonite as I recall.

Cheers!

Steve
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Bob Harman March 21, 2012 10:10PM
Colorful and very collectible CELESTINE crystals are found in geodes in Lawrence and Washington county quarries in Indiana. All 3 pix show 8 cm x 4 cm geodes containing 2.5 - 3.0 cm blocky celestine crystals with some minor calcites. The first pix is from the old, now flooded and extinct Mitchell quarry in Lawrence County. The 2nd and 3rd pix are from still active Salem quarry in Washington county. Many floater crystals of celestine from this quarry grace collections and museums around the world. Mineralogical Record had an article on the minerals of this quarry about 1983. Several local clubs still are lucky enough to gain yearly entrance to this quarry, but very hi quality finds are now few and far between.
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Stephen Rose March 23, 2012 07:32PM
Bob,

The geodes showing malachite are really interesting. I have only one Indiana geode showing chalcopyrite with malachite alteration associated and it is from the aragonite location on SR37, 5.25 miles north of Bloomington in Monroe County. What is more interesting, I didn't know about the chalcopyrite until the day before you posted your malachite pictures! It only took 48 years. I was looking for a new geode to photograph and found it in a box of inexpensive mixed things that I have been selling to kids over the years. I suppose that I had kept it for the ankerite and calcite but never took a close look at it. It is vintage 1964 and should have been noted in the 1966-1967 Rocks and Minerals article but was not.



Chalcopyrite, malachite (left center on quartz), ankerite, calcite and quartz geode. 4.5x4 cm. Chalcopyrite crystal approximately 1.0 mm. Circa 1964.



Here is the best I can do with my camera through a 10X lens for the little chalcopyrite with malachite.

Cheers!

Steve



Edited 2 time(s). Last edit at 03/24/2012 05:10PM by Stephen Rose.
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Bob Harman March 24, 2012 08:57PM
No discussion of Midwest geodes would be complete without talking about very large "field and stream" geodes. So, I went back and reviewed mindat's archive pages from the last several years and indeed there have been several posts, during that time, regarding these large geodes, usually involving their collector value or some such similar question. Here is my take and summary on the subject. These geodes are found in fields and stream beds. They can weigh from about 40 lbs to 350 lbs here in Indiana. They usually are collected and displayed UNOPENED and, when opened, are solid or have a relatively small cavity with dingy rusty/muddy appearance. They, only very very rarely, are nice and fresh inside. As such they have little collector value, being sold unopened (at lawn and garden shops) by the pound rather than by their inside appearance. Their uses therefore, include display, unopened, in rock gardens or around a home porch, as pictured here. Also, they are displayed, unopened, in museum hallways and entrances to geology exhibits in university geology buildings. These examples are usually donated to the museums or universities and never bought by the university or museum. So, as mentioned, they have little to no mineral or geode collector value as they are too bulky and heavy and ugly to display in a private collection or cart around to mineral shows etc. As such, for example, a 100 lb geode would only have a per pound weight value of about $50 - $100. I hope this summary answers some questions out there. BOB
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Bob Harman March 24, 2012 09:18PM
STEPHEN That is about what my chalcopyrites altering to malachite look like; they are hard to photograph and not very displayable. Also interesting that they all come from aragonite locales. Yours was along Indiana route 37 in Northern Monroe county and mine in Southern Monroe county. I think these are all in the Ramp Creek formation of limestone; if so, there is a small bit of copper in it...... Cheers BOB
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Stephen Rose March 25, 2012 12:08AM
Bob,

I had to look it up....nomenclature changes in the rocks. Ramp Creek fm is now what was the Lower Harrodsburg fm. Maybe a good exploration tool for you geode hunters?

Cheers!

Steve
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Stephen Rose March 25, 2012 03:35AM
I'll post one more, a bit smaller than those in Bob's last posting!



Baryte, SR37 about .75 miles north of Harrodsburg, Monroe County, Inidana.

Pale, grey-blue bladed crystals in a small quartz geode. The possibility that this is celestite was considered as strontionite is reported from this location. However, it does not seem likely as celestite is not reported as a geode mineral from this or any of the numerous locations around Harrodsburg. Overall size:4.5x6x4 cm. Baryte cluster is 0.8 cm tall. Circa:1965.

Cheers!

Steve
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Stephanie Martin March 25, 2012 04:51AM
Great stuff guys! Enjoying this thread. Who doesn't like geodes? Those malachites are way cool and those blocky celestines... they are celestial!

regards,
stephanie :-)
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Bob Harman March 25, 2012 02:19PM
Indiana geodes host a number of secondary minerals that are not commonly found. In addition to my previously pictured malachites and the chalcopyrite that I alluded to (and Stephen Rose pictured), here are several other rarely found minerals in Indiana geodes. The first pix is of SELENITE variety of GYPSUM. The needles are on quartz and adjacent to a calcite and barite. This geode is about 12 cm, from Monroe county, 2008. The second pix is of a small purple FLUORITE in a small 1.5 cm geode. I only have this one example and have never seen another, altho "it is reported to occur". From Harrison county, 2000. The third pix is of STRONTIANITE on quartz with adjacent barite. There are multiple white "puff balls" of strontianite; this one is also from Monroe county 1980s and again is the only one I have, but "reported to occur". Enjoy.......... BOB
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Stephen Rose March 26, 2012 05:10PM
Another small specimen from the SR37N (aragonite) roadcut 5.25 miles north of Bloomington in Monroe County. Collected in 1964/65.


Smythite/pyrrhotite inclusions in pale yellow baryte with dolomite and quartz. Geode opening 3x3 cm.


As above, magnified. Baryte crystal is 1.0 cm. long.

Smythite is quite common at this location and is almost always associated with pyrrhotite with one or the other being predominant in a given specimen. It is usually found as inclusions in calcite, rarely in baryte. One specimen of free-growing smythite was found during this period and xrd identified.*

Cheers!

Steve

*Bob, this one went to the Harry Sering geode collection as well.
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Bob Harman March 26, 2012 08:13PM
STEPHEN Smythite was first identified in Indiana geodes; I believe it is the only mineral first identified in Indiana. As you alluded to it is quite common, especially as 1mm six sided plates within barite crystals and occasionally in calcites as well. It was previously thought to be marcasite crystals. About 3 years ago, John Rakovan a geology professor from the University of Miami, Ohio requested some smythite from me as his students were working on a paper about it. I provided him enough for his research and, I believe, the paper was presented at the Rochester, NY symposium. In an upcoming post, I will show some pix of barite with smythite. CHEERS............BOB
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Kenneth Vaisvil March 27, 2012 03:59AM

I enjoyed the smythite discussion. I know goethite can be found in both Keokuk and Indiana geodes.
This photo is a geode from Clark County, Missouri - having the longest goethite needles I've ever found - the longest is 1/2".


This photo shows black goethite needles in a 3-1/2" diameter geode from Hancock County, Illinois.



And this is a photo taken through a microscope of a double terminated goethite crystal in the above geode. The dots appear to be micro rosettes of red hematite crystals. I can't recall the magnification used.

The black goethite crystals I have found in Indiana might be pseudomorphs after capillary marcasite because they have the sword blade shape instead of the pencil point shape like those above.
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Bob Harman March 27, 2012 12:06PM
The first pix is SMYTHITE in BARITES. The smythites are the 1mm six sided plates and were formerly thought to be marcasites. This geode represents one of my very first "modern" finds, from before 1995, and was prepared badly, but as I used polyurethane spray to stabilize it, I have never tried to undo it and re-prepare it. The second pix is of a 4.0 cm Brown County Indiana geode with GOETHITE. Note its similarity to the one Ken V posted. Geodes from Brown County tend to be small with micro minerals. The third pix is of a 9.0 cm geode containing groups of irridescent MARCASITES and questionable PYRITE on DOLOMITE. This is from Monroe County 2009.
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Stephen Rose March 27, 2012 05:58PM
Ken, those photos are really good. Those must be some of the bigger geode goethites around. Bob, great rocks! My experience with smythite is that it is much more commonly found in calcite, especially at the locality north of Bloomington (roadcut 5) with the good aragonite. It could be simply that there is so much more calcite than barite encountered there. It looks like the barite/smythite you show came from the Harrodsburg area; I'll have to take a closer look at some of my specimens.

Today, an Illinois specimen:


Kaolinite in geode with dolomite and quartz from Crystal Glen Creek, Hamilton, Hancock County, Illinois. 7.5x6x4.5 cm (larger half). Circa mid 1960's.

Cheers!

Steve
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Bob Harman March 27, 2012 08:46PM
DOLOMITE is one of the most common secondary minerals found in Indiana geodes, and other midwest geodes. It is found both alone and in varying combinations with other secondary minerals. In geodes from the In 56 road cuts in Washington County, dolomite overgrows quartz and the geodes become quite colorful. The dolomite saddle shaped rhombohedral crystals can vary from pearly pink thru all shades of reddish orange to brown FERROAN DOLOMITE and on to ANKERITE. Several colors can be present in the same geode as seen in these 2 pix. The first is of a large 18 cm geode and the second pix is of a 4 cm geode. More pix of this stuff coming up in the near future..........great pix everyone!!! BOB
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Bob Harman March 29, 2012 10:03PM
Three more interesting and unusual Indiana QUARTZ geodes. The first pix is of an esthetically pleasing evenly and delicately hematite colored tips of the quartz crystals in a 12 cm specimen. Almost always geodes with stained crystals are unappealing and not of display quality; some are even sold as "citrine", but are just rust stained ordinary quartz and not really of any enhanced value. The second pix is of a small 3.5 cm geode called a "pinkie". These geodes are always small and the crystals have a decidedly pink hue; not quite rose quartz, but pinkish hue never the less. Most also contain small pinkish gray calcites. They can even be recognized prior to opening as their outside is very lumpy bumpy, and when cleaned, is vaguely pinkish gray in color. The third picture is a very interesting 13 cm geode of crystalline quartz on blue chalcedony (microcrystalline quartz). These are very rare and, I suppose, an unusual variant of the dew drop diamond variety described by me with an earlier picture. CHEERS................BOB
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Kenneth Vaisvil April 03, 2012 01:53AM
Bob, thanks for showing me your fine collection again. Hope you don't mind me sharing the pictures I took of one of your Indiana smoky "dew drop diamond" geodes. The quartz dipyramids are as fine as any I've seen out of the Keokuk area.
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Stephen Rose April 05, 2012 01:22AM
Another from the 'aragonite' locality north of Bloomington in Monroe County, Indiana. The overall size is 8.5x7.5x6 cm but because of the thick inner layer of dolomite the opening is only 4.5x3 cm. Calcite rhombs with minor smythite-pyrrhotite on dolomite.



Cheers!

Steve
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Bob Harman April 09, 2012 07:36PM
Every field collector dreams of finding one or some very hi quality specimens.......stunners. Well, over the years some collectors' dreams do come true. In this case, the first pix is of one large Indiana geode that I found two years ago. It measures about 20 cm x 13 cm and is from a high banked stream bed in Washington County. There are mounds of pristine ARAGONITE on pristine QUARTZ. The second pix is of an Indiana geode found in May of 2005 at the Harrodsburg road cuts (see pix in "The Nature Thread") in Monroe County. It was found by a fellow collector and purchased by me. This geode measures about 19 cm x 18 cm and contains an isolated 4.5 very lustrous transparent BARITE and a nearby isolated 7cm CALCITE rhombohedral crystal. Both these geodes were recently shown to a high end dealer who was interested in acquiring them, but wanted to trim the interesting parts of both, thus sacrificing the geodes. Most of us have, at large shows, seen portions of amethyst "geodes" trimmed to show calcites etc or good crystal portions trimmed out of large Madagascar celestine geodes. These are then sold as "specimens" rather than their true geode type environment to enhance their values. To date, I have elected to keep these geodes intact and not trim the high quality areas from the rest of the geode. Enjoy..............BOB
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Bob Harman April 09, 2012 10:57PM
My case at the 2011 Cincinnati show. This case shows some of my display quality Indiana geodes from the route 56 road cuts just East of the town of Salem in Washington County. These geodes often have yellow through brick red DOLOMITES upon which significant CALCITES occur. Also found are SPHALERITES and occasional BARITES, a couple of which are pictured. As such, these geodes are routinely quite colorful and often medium to quite large in size. Ordinary QUARTZ geodes also are regularly found, but in only one layer near the road level. Collecting is best in mid winter thru early spring as the rock loosens up with freeze/thaw cycles. Collecting is poor thru the summer months, but as I write, a number of very hi quality specimens are currently (and at most times) still in the high wall about 12 to 25 feet up. Repelling down from the top or use of a lift at the roadside might reward a determined collector! But don't expect help or encouragement from the police or highway department! Whole geodes are quite uncommon as the rock layers scale off naturally splitting most geodes into slices or 2 halves as seen here in the case. All these were self collected as depicted, with none cracked open over the past 10 years or so. Enjoy...........BOB
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Rock Currier April 10, 2012 12:15AM
Bob,
So there are geodes from the mid west that are better than yard rock. Who would have guessed. Those are two really amazing geodes. I sure wish you would upload those and images of some of your other geodes to the mindat general gallery so I could put them in the Best Minerals articles. If you need help on how to do this uploading, you can read about it by clicking here: Uploading specimen images to Mindat.

Rock Currier
Crystals not pistols.
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Bob Harman April 10, 2012 11:09AM
ROCK I have not been ignoring your pleas for me to upload some images of my best and most unusual Indiana geodes to your permanent file site, but there are several situations that presently command much of my time. Also, I am not very computer literate, having had help walking me thru even these simple steps. I may get that help again when I have the time and then the uploading would begin. Thanks for your interest; watch for more pix in the coming weeks and months. BOB HARMAN
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Bob Harman April 10, 2012 05:22PM
For Indiana geode collectors, and indeed many midwest geode collectors, MILLERITE and its oxidation products including HONESSITE are highly sought after. The first pix is of HONESSITE (?) on QUARTZ in a 13 cm specimen from Monroe County. Its absolute identification is part of a rather jumbled classification of the oxidation products of millerite. Note the bright grass green color of the crystal sprays. The best spray actually just pokes out from beneath the quartz in the lower center of the photo. The second pix is of a 1cm symmetrical bright brassy MILLERITE spray nestled in a 9 cm Quartz geode from Monroe county. Both were found at the Harrodsburg road cuts. When Indiana state route 37 South of Bloomington was widened to 4 lanes in the early 1970s, quite a few high quality millerites (and barites, calcites etc) in geodes were found. I have talked with one of those collectors and he recounted his adventures collecting many geodes as the road work proceeded......what an adventure for him and his collecting buddies! The construction site is said to have swarmed with collectors on weekends. These specimens went to numerous museums and private collections. Visiting several museums on my travels, I have seen a couple of them, dated to that road widening time frame.
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Bob Harman April 12, 2012 11:09AM
In November of 2007 during construction of a small retention pond in a new housing subdivision near Bloomington, Indiana, very fresh geode bearing rock was exposed. I had 3 days to collect as the heavy equipment contoured the 1 acre site and crushed up the surface rock, then covering it with gravel. Now it is an extinct site intermittently filling with water after heavy rains. The geodes are quite distinctive, showing pearly pink dolomites upon which colorless to pale cream colored calcites occur. These often have a "satiny" surface patina, as seen in the second pix. Some out there who know Midwest USA minerals might see a resemblance of the first pix with Corydon Indiana quarry calcite and dolomite non-geode specimens. However, these are true geodes as all have a quartz rind and most show some very fresh crystalline quartz as shown in the second example. I gave one example to a friend and sold (regretfully !) one additional example at a local show; I believe only we three people have geodes from this short-lived site.
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Bob Harman April 14, 2012 12:56PM
These 3 geodes were found several years ago in my favorite ARAGONITE location in southern Monroe County, Indiana. The first pix shows an 10 cm x 4.5 cm specimen with the largest ARAGONITE grouping bridging the cavity. A smaller spray can be seen in the background as well as scattered hemispheric coatings on the QUARTZ crystals. The second pix shows halves of 2 geodes one is 7 cm; the smaller is 3.5 cm. Each shows advanced decomposing FERROAN DOLOMITE/ANKERITE, still crystalline, with some ARAGONITE sprinkled on the tips of the underlying crystals. Note the similarity to the old LIMONITE classification, especially in the broken crystal areas.The third pix is a close up of the geode on the right in picture #2. Enjoy......BOB
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Bob Harman April 17, 2012 09:24PM
The accompanying pix show an unusual geode type found in Indiana and also in Kentucky and Illinois. They are geodized fossils. One theory of geode formation involves fossils decaying in the mud and their void being slowly replaced by a quartz rind and a central cavity. However these form, they are quite interesting and, in Indiana, found most commonly in Monroe, Washington and Lawrence counties. They are of gastropods, brachiopods, cephalopods, horn corals, crinoids and various shells. They range from several centimeters to many centimeters in size in some locations. The very best ones, as shown here, show remaining good fossil detail with parts of the original shell incorporated into the geode. Most are examples solid, but occasional examples are hollow with Quartz crystals as in an "ordinary or usual" quartz geode. For a hollow example, see my previous pix on page 2 of this thread with a smoky dew drop diamond variety. Enjoy..................BOB



Edited 1 time(s). Last edit at 04/17/2012 09:29PM by BOB HARMAN.
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Rock Currier April 18, 2012 12:38AM
Bob,
You should really upload your images to the Mindat Image gallery. Then you could put them to gather as an article or as a Best Minerals article. Did you see the one that Harjo Neutkens did on Schalenblende?

http://www.mindat.org/mesg-85-134773.html

Rock Currier
Crystals not pistols.
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Bob Harman April 18, 2012 01:21PM
Sulfides as secondary minerals in Indiana geodes are quite common and include SPHALERITE, PYRITE, MARCASITE, and MILLERITE. Also there are less common oxidation minerals and minor minerals. Millerite and marcasite examples have been previously pictured and pyrites tend to be small and not very showy. However, SPHALERITE can be quite showy. The best come from Monroe and Washington counties. They are quite common in geodes from the Harrodsburg roadcuts, but are very rarely found as free standing crystals; most being cleavage portions embedded within calcite and dolomite in solid geodes as pictured on the right of the second picture. Good free standing crystals up to 3 cm occur at the Indiana route 56 road cuts in Washington county and one is pictured in the first photo. The best from Monroe county seem to occur in geodes from the Unionville railroad cut, Northeast of Bloomington. A 1 cm example is on the left of the second photo.
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Kenneth Vaisvil April 19, 2012 01:37AM
Bob, excellent photos & geodized fossil specimens !

I happened to find my best ever chalcopyrite on calcite Keokuk geode in Lee County, Iowa on my last collecting trip. The geode is 11 cm in diameter and the largest group of interjoined/twinned chalcopyrite crystals in the last photo is 1 cm across. You will also see some enlogated cubes of pyrite or marcasite in it as well.
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Bob Harman April 21, 2012 08:08PM
In many of my previous pix of Indiana geodes (but by no means all of them), I have shown one secondary geode mineral in addition to the QUARTZ. In fact most display quality Indiana geodes have various combinations of 2 or more secondary minerals present.These 3 pix show BARITE and DOLOMITE in the quartz geodes. All three are from the Harrodsburg road cuts in Monroe county. The first pix shows a 12 cm x 7 cm geode containing several DOLOMITE groupings along with a stout 2.8 cm x 3.0 cm color zoned barite. There is a visible internal crystal fracture in the barite which is quite common. Found in February of 2007. Pix number 2 shows a 14 cm x 9 cm oval geode with orange DOLOMITE groupings and rim surrounding innumerable jumbled BARITES. Of interest is the fact that the barites exist mostly in the lower (bottom) portion of the geode, probably due to gravity and their weight during formation. This half fell to the roadside after a freeze/thaw episode in February 2000, while the other half remained slowly deteriorating in the limestone hi wall about 12 feet up for several years. Look closely and note the fossil crinoid stem sections in the adjacent limestone. Finally, picture 3 shows a 6 cm x 5 cm specimen with pale creamy DOLOMITES and pristine pale yellow transparent BARITES. It was found in the 1970s or 1980s by another prominent midwest collector and purchased by me about 2009. ENJOY......BOB



Edited 1 time(s). Last edit at 04/21/2012 08:15PM by BOB HARMAN.
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Bob Harman April 24, 2012 08:38PM
Two more Indiana geodes from Monroe County. The first pix is a 20 cm example with CALCITES, including a 5.5 cm one, groups of BARITE and groups of interesting dark chocolate brown FERROAN DOLOMITES. Acquired by me from a fellow collector who found it in 2008. The second pix is of a 19 cm x 15 cm example with a complex group of CALCITES, BARITES, a few DOLOMITES and a small SPHALERITE (seen in the lower left of the photo). Acquired in 2004. These 2 examples show additional examples of the complex mixtures of secondary minerals commonly found in Indiana geodes
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Bob Harman April 28, 2012 03:49PM
Several other spots in southern Monroe County, Indiana produce geodes quite similar to those found at the nearby Harrodsburg road cuts (several examples already previously pictured here). Also, see some recent pictures of the Harrodsburg road cuts in the "Nature Thread". The first picture is a 17 cm x 14 cm geode with several CALCITES, including two 5 cm rhombohedral examples, adjacent 1.5 cm to 2.5 cm BARITES and a few small DOLOMITE groups are also present. This example was found and extracted with a stone saw by a fellow collector in 2008 at the "Barite Hill" locality. The site's name is only used by geode collectors as many barite containing geodes have been found there. This is a very short road cut whose overhang is now collapsing and may make the site extinct within the next several years. The second pix shows 2 geodes, the larger of which contains a flat lying 6.5 cm CALCITE and a nearby 2.5 x 3.0 cm free standing pale yellow to colorless BARITE. Several small calcites also occur. This geode is from the early1980's at the Monroe Lake spillway when collecting apparently was allowed. Some time after 1990, collecting of geodes and fossils at this site and along Lake Monroe shorelines became forbidden. Parenthetically, here is an interesting story about collecting along the lake shoreline. About 11 years ago an Indiana University graduate student who collected fossils found an invertebrate specimen that neither he nor anyone else recognized. He showed it all around and it was eventually sent off to an out of state expert in that fossil area. It was considered a significant new species and written up in (I think) the periodical "Nature" about June 2002. He then made the mistake of showing all this to the local Bloomington newspaper and a big article appeared about the fellow and his new local fossil species find from the lake shore. Well, within several days the Indiana conservation officers came knocking on his door and gave him 2 options. Be charged with illegal fossil collecting or donate the specimen to the museum and stop collecting. Not positive, but I think his specimen now resides in the Smithsonian. Currently you need a collecting permit, but, as far as I know, no one manages to get one!. CHEERS.........BOB
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