Prehnite - United States of America

Click here to view Best Minerals Prehnite - Australia to United Kingdom. Click here to view Best Minerals P, click here to view and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.



Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?



Prehnite
USA
Connecticut, East Granby, Roncari quarry (Tilcon quarry)

Prehnite, 9cm wide	© 2002 John H. Betts

Prehnite & Calcite, ~7cm wide	©

Prehnite & Calcite~7cm wide	©

Prehite & Datolite, ~4cm tall	©

Prehnite & Babingtonite ~2cm wide	© Paul Gilmore

Better known from this quarry are its specimens of Datolite specimens, but the quarry has produced some very fine combination specimens. I know one old ex quarry worker that has a whole basement full of specimens from this quarry that will someday come to market or be thrown out on the dump.
[Rock Currier]


Prehnite
USA
Connecticut, Hartford Co., Farmington




Prehnite
USA
Connecticut, Hartford Co., Simsbury, Talcott Mountain State Park, Talcott Mountain




Prehnite
USA
Connecticut, Litchfield Co., Woodbury, O & G Woodbury Quarry (Orenaug Quarry; O & G No. 1 Quarry)

Prehnite on Calcite, 4.1cm wide	© Henry Minot 2008

Prehnite
USA
Connecticut, New Haven Co., Southbury, O & G Southbury Quarry (Silliman Quarry; O & G No. 2 Quarry)

Prehnite, 5.9cm wide	© 2001 John H. Betts

Prehnite, 4cm tall	© Martins da Pedra

Prehnite & Quartz, 4cm wide	© Martins da Pedra

Prehnite
USA
Connecticut, Tolland Co., Coventry, US Route 6 Willimantic Bypass expressway road cuts

Prehnite 1.2cm tall	© 2011 Harold Moritz

Prehnite
USA
Maine, Knox Co., Thomaston, Old Country Road locality




Prehnite
USA
Maine, Washington Co., Calais




Prehnite
USA
Massachusetts, Hampden Co., Westfield, Lane & Son traprock quarries

Prehnite, 7cm wide	© 2001 John H. Betts

Prehnite, 7cm across	© 2001 John H. Betts

Prehnite 10.4cm wide	© Rob Lavinsky

Prehnite
USA
Michigan, Houghton Co.




Prehnite
USA
Michigan, Keweenaw Co.

Prehnite 4.8cm wide	© C. Stefano '12

.

Prehnite & Copper 4.5cm wide	© Paul T. Brandes

Prehnite
USA
Michigan, Keweenaw Co. Mohawk, Iroquois Mine




Prehnite
USA
Michigan, Keweenaw Co. Phoenix, Phoenix mine




Prehnite
USA
Michigan, Keweenaw Co. Phoenix, Cliff mine




Prehnite
USA
Minnesota, St. Louis Co., Knife River

Prehnite after Laumontite 4cm wide	© Rob Lavinsky

Prehnite 9cm wide	© JKNash

Prehnite
USA
New Hampshire, Merrimack Co., Warner, Prehnite locality




Prehnite
USA
New Jersey, Bergen Co., Fort Lee



Between 1961 and 1962 excavation work occurred in the Palisade Sill on the New Jersey side of the George Washington Bridge at Fort Lee to accommodate a twelve lane highway and its approaches. In an area off Route 4, approximately 1.2 km West of the toll booths, blasting of the diabase exposed mineralized veins, some to a meter wide, containing minerals in micro to cabinet-sized specimens. Mostly known for its fine micro crystals of titanite, prehnite was also collected in globular clusters and isolated spheres to nearly 2.5 cm, typically associated with actinolite, albite, chlorite, epidote, pyroxene and titanite. The prehnite was a light green in color with a waxy appearance.
[Frank Frank Imbriacco 2012]


Prehnite
USA
New Jersey, Essex Co., Livingston, Riker Hill

Prehnite, 4.4cm wide	© Frank A. Imbriacco III

.

Prehnite, ~7cm across	©

Prehnite, ~9cm across	© EAS 2008

Riker Hill was not a quarry but rather a housing tract. In 1970 a housing development adjacent to Fawn Drive atop Riker Hill in the Third Watchung Basalt. Blasting was necessary to remove rock for the construction of foundations and utility trenches. Mineralization occurred in amygaloidal cavities in the basalt. Specimens of prehnite were and consisted mostly lime green mammilary crusts without much of gem quality. The best that came out was often closely associated with Calcite. In the peak years, a local collector named Joe Rothstein had very impressive Prehnite & Calcite combination specimens. One unusual feature of this location was that white Prehntie was as common there as the green & yellow varieties. Not sure why white Prehnite was common but is was beautiful when combined with Pumpellyite or Chlorite. Basalt was always the matrix here and the overall best specimens were collected at the end of the cul de sac road that was being constructed.
[Eric Stanchich and Frank Imbriacco 2009/2012]


Prehnite
USA
New Jersey, Essex Co., Montclair Township, Upper Montclair, McDowell's Quarry (Osborne and Marsellis Quarry)




Prehnite
USA
New Jersey, Passaic Co., Haledon, Braen Quarry (Braen Stone Industry Quarry; Sam Braen Quarry)

Prehnite, ~11cm wide	© EAS 2008

Prehnite at the Braen Quarry in Haledon is mostly confined to the scoria capped amygdaloidal horizon immediately above the pillow basalt which rests on the underlying Feltville Formation mudrock. It was also encountered in cavities within a diapir located on a wall adjacent to an access road near the bottom of the pit. Prehnite occurs as pale green botryoidal coatings, in spherules up to 2.5 cm and in spheroidal clusters. It is commonly associated with calcite, datolite, sulfides and rarely with zeolites.
[Frank A. Imbriacco III 2009]


Prehnite
USA
New Jersey, Passaic Co., Paterson, Interstate 80 roadcut




Prehnite
USA
New Jersey, Passaic Co., Little Falls Township, Great Notch



The Great Notch quarry is more well known for practically every other traprock mineral except Prehnite. Prehnite finds were not rich and usually limited to associated spheres with other traprock minerals.
[Eric Stanchich 2009]


Prehnite
USA
New Jersey, Passaic Co., Paterson, Hoxie's Quarry




Prehnite
USA
New Jersey, Passaic Co., Paterson, Lower New Street quarry

Prehnite after Anhydrite ~18cm wide	©

Prehnite, 9.5cm wide	© Frank A. Imbriacco III

Prehnite snake heads ~5cm tall	©

Prehnite after Anhydrite ~7cm wide	©

Prehnite casts, 10cm wide	© Frank A. Imbriacco III

Lower New Street quarry is one of the old time localities that has been abandoned for years and though plans to build on the site were made, the quarry is still there and local collectors manage to find a few things from time to time. Lower New Street is the quarry that produced the best examples of the so called Prehnite snake head casts after anhydrite that collectors of New Jersey trap rock minerals revere. Ernest Weidhaas of Mt. Vernon New York seemed to have the lions share of the best ones I saw and some of the best are pictures above including the great one (the 18 cm one at the top of this localitys images) that he paid the equivalent price of a new care back in the 50s. In fact Ernest told me that he had offered a new ford car for the specimen to the guy who dug it and it became a treasured specimen to the whole family. After the death of the owner he went to the house and ask if he could buy the specimen and was told "Oh no, there is a crazy rich man in New York who offered a new car for the specimen." He told the family he was the man and they eventually sold him the specimen.

Notice that some of the Prehnite snake head casts and some of the other prehnite specimens look dirty. They have little speckles of stuff on them. You may also notice that many of my other pictures (the ones with the little one inch brass scale bar at the bottom) look dirty. On some of them you can actually see dirt down in the cracks of the specimens. That is because there were taken of old time specimens in old collections. More than about 20 years ago, collectors, dealers and curators did not have the wonderful little high pressure "fabric" guns that shoot streams of high pressure water that are commonly used today to clean up specimens and are so adroit at ferreting dirt out of every little crack. About the best they had back then were little brushes of various kinds that were really not very good at cleaning up specimens. I took these pictures mostly in museums and old collections, and it was not practical to clean them or often polite to suggest that their specimens were dirty and needed cleaning. Many of todays dealers make a lot of money by doing nothing more than blasting the dirt off of old specimens.
[Rock Currier 2009]


Prehnite
USA
New Jersey, Passaic Co., Paterson, Upper New Street Quarry (Burger's Quarry)

Prehnite casts, 9cm wide	© Frank A. Imbriacco III

Prehnite, 6.7cm wide	© Rob Lavinsky

Prehnite "finger", 6.5cm tall	© Rob Lavinsky

Prehnite & Thomsonite ~7.5cm wide	© EAS 2010

Prehnite
USA
New Jersey, Passaic Co., Prospect Park, Prospect Park Quarry (Sowerbutt Quarry; Vandermade Quarry; Warren Brothers Quarry)

Prehnite after glauberite ~10cm wide	©

Prehnite fingers 11.3cm wide	© Frank A. Imbriacco III

Prehnite, 10.4cm wide	© Frank A. Imbriacco III

Prehnite & minor Laumontite ~12cm wide	© EAS 2008

Prehnite & Calcite ~15cm wide	©

Prehnite & Mesolite 15.5cm	©

Prehnite & Pectolite ~7.5cm wide	©

Prehnite & Natrolite ~7.5cm wide	© Kosnar

This locality is probably the best known of all the New Jersey trap rock quarries. It has been producing specimens for more than 75 years. The quarry has produced many tons of prehnite specimens as well as fine Datolites, Analcime, Pectolites, Thompsonites as well as good Calcites, Natrolites and others. It has even produced at least one amazing small wire silver specimen. This quarry and others in the region have attracted many field collectors and many of these collectors have gone on to become well known dealers, curators and authors. George Kunz, John Sinkankas, Charles Key, and Richard Kosnar are just a few of the hoard of the better known people that the trap rock quarries have produced.

Often the prehnite specimens from this quarry show signs of being casts after anhydrite and glauberite that are common in the amygdaloids of the Watchung trap rocks and crystallized before the "zeolite" minerals. The anhydrite casts are rectangular in cross section, often very flat rectangles and often look like knife slashes on the backs of the Prehintie specimens. The glauberite casts are less often seen and their casts are often diamond shaped. Both kinds can be seen in specimens from this and other quarries.
[Rock Currier 2012]

The world famous Prospect Park Quarry, which ceased blasting in 2011 and is being backfilled for a future housing development, produced copious amounts of prehnite throughout its 100+ year existence. Prehnite was deposited within several structures of the quarry including: 1) diapirs, 2) an amgydaloid and 3) pillow basalt. At Prospect Park numerous dome-shaped diapirs have been identified starting within the lower colonnade of the first flow and extending upward into the overlying entablature. Carpets of prehnite epimorphs after anhydrite line the many openings visible near the upper interior of these structures. An amygdaloidal horizon lies at the top of the lower flow in which prehnite was deposited as thin botryoidal linings. Although the prehnite is average in quality compared to that from other areas of the quarry, the formation of greenockite microcrystals on the prehnite makes it highly desirable. Some of the quarry's finest prehnite comes from the pockets within the pillow basalt located in the second flow at the highest levels of the quarry. Prehnite there has been collected as epimorphs after anhydite, bright green botryoidal linings and isolated spheres in conjunction with zeolites and their associates.
[Frank Imbriacco 2009]


Prehnite
USA
New Jersey, Passaic Co., West Paterson, Pumping Station, McBride Ave. & Browertown Rd.

Prehnite & Calcite, 12cm wide	© Frank A. Imbriacco III

Prehnite, 8cm wide	© Frank A. Imbriacco III

Prehnite ~15cm wide	© EAS 2010

In late 1986, blasting occurred adjacent to the intersection of McBride Avenue and Browertown Road for a sewer pumping station. After a 30' deep trench was excavated, Chris Laskowich discovered a 5.4 m long tube with two 1.8 m long off shoots near the bottom half of this hole. The tube was lined with thick botryoidal prehnite and prehnite fingers after anhydrite, up to 6.4 cm, associated with etched calcite rhombs and chalcopyrite. Many hundreds of specimens were removed from this location by Chris and other collectors during a three month period. The best of the prehnite from this locale is unique in New Jersey due to its smooth, glossy finish and bright blue-green color.
[Frank A. Imbriacco III 2009]


Prehnite
USA
New Jersey, Passaic Co., West Paterson, Union Building and Construction Quarry (UBC Quarry; Tilcon Quarry)

Back side of left	© Rob Lavinsky

Prehnite, Prehnite fingers, 5.5cm wide	© Frank A. Imbriacco III

Prehnite
USA
New Jersey, Somerset Co., Bernards Township, Millington Quarry (Morris County Crushed Stone Co. Quarry; Tilcon Quarry)

Prehnite on matrix, 9.5cm wide	© Frank A. Imbriacco III

Prehnite & Natrolite, 5cm wide	© EAS 2008

Prehnite & Natrolite 5.5cm wide	©

The Millington Quarry, now a defunct locale, produced a large amount of prehnite specimens. The primary mineralization occurred within an approximately 30 m thick amygdaloidal horizon at the top of the first flow, extending into the basal area of the second or overlying flow. Prehnite was found in the middle of the amygdaloidal layer, beginning near the upper distribution of pectolite and continuing to just below the scoria. Although prehnite was considered common, many of the pockets were lined with a thin crust. The best prehnite specimens, in the form of thick botryoidal linings or isolated spheroids, were highly localized. Some of the finest prehnite was recovered during the final years of collecting in 2006 and 2007 in the center of the quarry.
[Frank A. Imbriacco III 2009]


Prehnite
USA
New Jersey, Somerset Co., Bridgewater Township, Chimney Rock Quarry (Houdaille Industries Quarry; The Bound Brook Quarry; Stavola Industries Quarry)



This localit is not well known for it's Prehnite which was found in veins and usually dried out and crumbly. The color was usually pastel green. Only one collector, Robert Drift, was able to retrieve more attractive Prehnite spheres directly on basalt matrix, but this find was very limited as far as quantity.
[Eric Stanchich 2009]


Prehnite
USA
New Jersey, Somerset Co., Watchung, Fanwood Crushed Stone Co. Quarry; Scotch Plains Quarry; Weldon Quarry)

Prehnite after glauberite, 10.3cm wide	© Frank A. Imbriacco III

Prehnite & Calcite 12.5cm wide	© Frank A. Imbriacco III

Prehnite after glauberite 8.6cm wide	© Frank A. Imbriacco III

Prehnite is distributed in a central, horizontal band of the amygdaloids located at the top of each of the three flows exposed at the Fanwood or Weldon quarry in Watchung. Most of this material is in the form of thin crusts or isolated small spheres which are either light green, vivid green or occasionally yellow in color. A small percentage of the prehnite in these horizons will form thicker botryoidal linings or spherical groups which can be quite attractive. The best prehnite is found in diapirs, as coined by Puffer and Laskowich, in the basal columnar basalt of the second flow. These large dome-like structures contain a myriad of irregularly shaped cavities of varying size. Three of the best known diapirs were located by Mark Bianch; the first in late 1987; the second in 2002 and the third in 2007. All contained prehnite after glauberite or rarely prehnite after anhydrite, each with a slightly different appearance. The 1987 find consisted of mainly two large voids at the base of a bench, filled with a light green prehnite, some covered with calcite crystals, to 5 cm or greater. The largest epimorphs take the shape of french fries. The 2002 diapir, located half-way up the side of a bench, consisted of at least 10 cavities. Many hundreds of specimens were recovered. One of the smaller prehnite pockets was coated with acicular natrolite crystals, up to 2 cm. The 2007 diapir was found in a wall approximately 3 m above a quarry access road. Although the formation contained numerous cavities, few quality specimens were collected. Prehnite from this pocket was unique. Many of the pieces were darker green in color and quite thick, similar to prehnite from the Paterson area.
[ Frank A. Imbriacco III 2012]
This quarry has been productive of mineral specimens for years and well know for producing chocolate brown heulandite crystals up to about 3 cm and stilbite spheres up to 6 cm in diameter, some of them bright orange, but probably the best things the quarry has produced are specimens of prehnite casts after heulandite. The first pocket in the quarry was found back in the late 1980s Mark Bianchi and this pocket produced hundreds of specimens but of somewhat lighter colored prehnite that the more recent one in 2003 or 4. This pocket was actually a string of interconnected pockets that was collected over a period of about a year. It was located up about 15 feet on the east wall of the quarry and ladders had to be used to reach and work on the pockets. Several hundred good specimens were collected.
[James Zigras 2009]


Prehnite
USA
North Carolina, Catawba Co., Martin Marietta Quarry (11th Street Quarry), Hickory




Prehnite
USA
North Carolina, Cleveland Co., Kings Mountain District, Foote Lithium Co. Mine (Foote Mine)




Prehnite
USA
Pennsylvania, Lehigh Co., Coopersburg



This locality only produced a few specimens. I managed to find one for sale in a collection at Wards in Rochester, New York years ago. I gave it to Arthur Montgomery and though he wrote the Minerals of Pennsylvania, he did not have one in his collection or in the collection he curated at Lafayette college in New Jersey and was very happy to have one. We need someone to tell us about the specimens from this quarry.
[Rock Currier 2011]


Prehnite
USA
Rhode Island, Providence Co., Cumberland, Manville Quarry (Todesca Quarry; Forte Brothers Quarry)

Prehnite 8cm wide	©

Prehnite
USA
Virginia, Fairfax Co., Culpeper Basin, Centreville, Fairfax quarry (Centreville Quarry; Sisslers Quarry

Prehnite ~2cm diameter	©

Prehnite ~4.5cm wide	©

This quarry is famous for probably the best apophyllite specimens ever found in the USA. Sometimes these slightly complex flower like white Apophyllites of up to 15 cm were found growing on a base of nice green prehnite. These were all collected by amateur collectors and though the find produced several hundred specimens, they have all gone away and are highly cherished by those collectors who have them. John Medici got collected some of the best ones. The pocket also produced some few wonderful prehnite specimens. Some were complete spheres of prehnite that had ridges around their equator and have sometimes been described as flying saucers or Roman helmets. The often had find black needles of actinolite or some black hair like amphabole mineral growing in them, sometimes to the point that the prehnite was almost black. One collector who collected in the pocket said that part of the pocket was filled with masses of this hair like material and some matrix specimens that he removed from the pocked he could turn upside down and shake these prehnite balls out of the hair.


Prehnite
USA
Virginia, Culpeper Co., Mitchell, Cedar Mountain Stone Corp. Quarry (A. H. Smith quarry)




Prehnite
USA
Virginia, Fauquier Co., Bealeton, Luck Stone Quarry (Luckstone Quarry)

Prehnite 5cm wide	©

Prehnite
USA
Virginia, Loudoun Co., Conklin, Bull Run Quarry

Prehnite, Calcite & Apophyllite 3.5cm	© Robinson

Prehnite 12.5cm wide	© Harold (Hal) Prior

Prehnite
USA
Washington, Snohomish Co., Sultan District, Sultan Basin, Vesper Peak

Prehnite on Grossular 5.1cm wide	© Rob Lavinsky

Click here to view Best Minerals Prehnite - Australia to United Kingdom. Click here to view Best Minerals P, click here to view and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Last picture selection, November 2012 Rock Currier

Rock Currier
Crystals not pistols.



Edited 71 time(s). Last edit at 12/17/2012 12:42AM by Rock Currier.

The first draft of the Best Minerals article on Prehnite has been completed with about 230 images. Any correction or suggestions for revisions or additions would be appreciated. Especially welcome would be addition from people with first hand knowledge of the many localities that we have no knowledge of, only the pictures that have been uploaded to Mindat.

Rock Currier
Crystals not pistols.

Rock,

I reviewed it thoroughly....very nice....really enjoyed it.

I want to preface this email by telling you....that Prehnite is absolutely....by far...my favorite mineral in the world. Obviously, living here in NJ....and collecting in the field at least 2 times a week for ten years......I got seriously hooked on Prehnite. At one time, my personal collection had over 650 NJ Prehnites....before I began selling off some of them.

Here is what I can do for you.

1. You have the pictures covered......although on your Lower New St pictures.....I had hoped you would have included my large Prehnite with fingers. It is specimen #2 in my collection...found in 2004...from a huge pocket I found there. The find sent a shockwave through the local mineral community. I kept 3 great specimens....and sold in excess of $5,000 in snakehead prehnite from my garage in 72 hours after the find. Even so, the amount of rock I need to move to duplicate the find is so great.....that I have not had the time to go back and try again.

2. In your description for Prospect Park: The quarry is being closed in 2011 and handed over to builders. It is currently being back-filled at a very fast rate. Also....and I am not trying to bring any glory to myself.....but in the past 10 years collectors like James Zigras, Curt Hennig, Mark Bianchi, Bryan Davis, and myself...Eric Stanchich....have all found significant Prehnite pockets that yielded world class specimens.

3. Upper New Street - Prehnite is found througout the quarry. Forms include spheres to 3/4 inch, in covered plates, as well as a variety of casts. While the casting is not as good as lower new st....it did produce a limited amount of snakeheads. Prehnite is found with a variety of associated minerals like Heulandite, Chabazite, Quartz, Apophyllite, Gmelinite, Laumontite, Calcite, Pectolite, Hematite, Thomsonite, & Quartz. As recently as 2008, a world class pocket measuring 3 feet long, 2 feet wide, and 10 inches tall of Prehnite spheres on Calcite was discovered and collected.

4. Braen's Quarry Haledon - The quarry was completely covered with an extremely thick layer of columnar basalt which was almost devoid of minerals. Active quarrying commenced in the 1960's.....1968. Yet, no major mineral finds were ever reported until the late 1990's. The underlying zone was pillow basalt....and yielded some great minerals. The Prehnite occured in a scoracious basalt layer between of overburden columnar and the underlying pillow basalt. The Prehnite finds here were decent to good specimens....and far outshined by the world class Stilbite and Stellerite specimens that the quarry produced.

5. Millington - The quarry was abundant with Prehnite....although pockets rarely reached the size of those found at Paterson or Prospect Pk. Typically, pockets were 6-8 inches across.....and yielded mass Prehnite as well as isolated spheres that commonly has associated Calcite. The quarry had three flows of lava......and the bottom and middle flows yielded almost all of the Prehnite. Pockets were found is very close proximity to one another. On more than 20 occasions, I personally stripped the wall of overburden rock to reveal 5-6 Prehnite pockets at once.

6. UBC Quarry - Very little quality minerals came from this locale. Two notable collectors, Chris Laskowich and Mark Bianchi, displaying admirable perserverance, were able to collect a handful of quality specimens. The Prehnite occured almost exclusively in lava diapirs: where underlying basalt extruded up through overburden basalt layers. The formation looks like a giant bubble.....sometimes 15-20 feet across. The quarry produced extremely limited specimen of some nice layered Prehnite cast specimens, world class spheres directly on basalt matrix, as well as very notable Datolite & Prehnite combinations specimens.

7. Hoxie's Quarry - So little is known about this quarry that almost all the information we have today came from the essay "A Remarkable Mineral Locality (Hoxie's Quarry, Paterson, NJ.) by Ehrman, A. H.". Evidentally, the quarry opened in the mid 1860's to support to booming local road construction projects. The quarry was located in what is today very close to the downtown Paterson business district. The quarry closed in 1891. Prehnites of magnificent luster and thickness were reported to have been found in relative abundance. World class Chabazites and Chabazite/Prehnite combinations specimens were also reported. Minerals from this locale are beyond scarce as it is generally believed that 95% of what was collected there has been lost.

8. I have several calls out to experts on Prehnite at Boundbrook, Great Notch, and Livingston. Give me a few hours to collect that info and I will forward it to you ASAP.



If you need anything else....do not hesitate to contact me.

Regards,


Eric Stanchich

1. Boundbrook - Not well known for it's Prehnite which was found in veins and usually dried out and crumbly. The color was usually pastel green. Only one collector, Robert Drift, was able to retrieve more attractive Prehnite spheres directly on basalt matrix, but this find was very limited as far as quantity.

2. Great Notch - More well known for practically every other traprock mineral except Prehnite. Prehnite finds were not rich and usually limited to associated spheres with other traprock minerals.

3. Riker Hill - A abundant source of Prehnite. Specimens were mostly mammilary in form with lime green color without much gem quality. The best that came out was often closely associated with Calcite. In the peak years, a local collector named Joe Rothstein had very impressive Prehnite & Calcite combination specimens. One unusual feature of this location was that white Prehntie was as common there as the green & yellow varieties. Not sure why white Prehnite was common but is was beautiful when combined with Pumpellyite or Chlorite. Basalt was always the matrix here and the overall best specimens were collected at the end of the cul de sac road that was being constructed.


Keep in touch!!!

Regards,


Eric Stanchich

Rock Currier
Crystals not pistols.



Edited 1 time(s). Last edit at 06/16/2009 07:53PM by Rock Currier.

Hey Rock; aren't you forgetting about the classic prehnites studded with copper crystals from the Keweenaw Peninsula of Upper Michigan??? I don't have any photos of the specimens I have, but I will work on some in the coming weeks...

Paul, Get me a good photo of one and Ill put it in.

Rock Currier
Crystals not pistols.

Rock,

When viewing this article I see pictures over text areas, a bug in the layout perhaps ? Areas to look at are ...

China, Germany Rhineland, India, Italy Aosta Valley, Russia, South Africa, Spain & USA NJ & NC.

Debbie,
Are you by any chance using the new Google Chrome browser? That is the browser I am using. I have it installed on my home computer(s) and the one I use down at my warehouse. I noticed the same problem with the Prehnite article down at work and thought I was going crazy. When I checked the article using Windows internet explorer and Firefox there was no problem also, only using Chrome on my computer at work. I eventually figured out. I fixed the problem in the Google Chrome browser by accessing and adjusting the zoom control at the top of the browser by clicking on the little icon that looks like a little blank piece of paper with the top right corner folded over. If the zoom is too large I got the overwriting and image alignment problems it sounds like you are having, but once adjusted, they all went away.

Rock Currier
Crystals not pistols.

Rock,

Yes I am using Chrome, all sorted now.

Thank You !!

Dear Rock:

I have updated the following information pertaining to several of the New Jersey prehnite locations listed in your article.

1) The top left photo "Prehnite casts, 10 cm wide," pictured under the Upper New Street quarry entry, is actually from Lower New Street quarry. It is Mindat photo 96693.

2) The Millington Quarry, now a defunct locale, produced a large amount of prehnite specimens. The primary mineralization occurred within an approximately 30 m thick amygdaloidal horizon at the top of the first flow, extending into the basal area of the second or overlying flow. Prehnite was found in the middle of the amygdaloidal layer, beginning near the upper distribution of pectolite and continuing to just below the scoria. Although prehnite was considered common, many of the pockets were lined with a thin crust. The best prehnite specimens, in the form of thick botryoidal linings or isolated spheroids, were highly localized. Some of the finest prehnite was recovered during the final years of collecting in 2006 and 2007 in the center of the quarry.

3) Prehnite is distributed in a central, horizontal band of the amygdaloids located at the top of each of the three flows exposed at the Fanwood or Weldon quarry in Watchung. Most of this material is in the form of thin crusts or isolated small spheres which are either light green, vivid green or occasionally yellow in color. A small percentage of the prehnite in these horizons will form thicker botryoidal linings or spherical groups which can be quite attractive. The best prehnite is found in diapirs, as coined by Puffer and Laskowich, in the basal columnar basalt of the second flow. These large dome-like structures contain a myriad of irregularly shaped cavities of varying size. Three of the best known diapirs were located by Mark Bianch; the first in late 1987; the second in 2002 and the third in 2007. All contained prehnite after glauberite or rarely prehnite after anhydrite, each with a slightly different appearance. The 1987 find consisted of mainly two large voids at the base of a bench, filled with a light green prehnite, some covered with calcite crystals, to 5 cm or greater. The largest epimorphs take the shape of french fries. The 2002 diapir, located half-way up the side of a bench, consisted of at least 10 cavities. Many hundreds of specimens were recovered. One of the smaller prehnite pockets was coated with acicular natrolite crystals, up to 2 cm. The 2007 diapir was found in a wall approximately 3 m above a quarry access road. Although the formation contained numerous cavities, few quality specimens were collected. Prehnite from this pocket was unique. Many of the pieces were darker green in color and quite thick, similar to prehnite from the Paterson area.

4) Prehnite at the Braen Quarry in Haledon is mostly confined to the scoria capped amygdaloidal horizon immediately above the pillow basalt which rests on the underlying Feltville Formation mudrock. It was also encountered in cavities within a diapir located on a wall adjacent to an access road near the bottom of the pit. Prehnite occurs as pale green botryoidal coatings, in spherules up to 2.5 cm and in spheroidal clusters. It is commonly associated with calcite, datolite, sulfides and rarely with zeolites.

5) In late 1986, blasting occurred adjacent to the intersection of McBride Avenue and Browertown Road for a sewer pumping station. After a 30' deep trench was excavated, Chris Laskowich discovered a 5.4 m long tube with two 1.8 m long off shoots near the bottom half of this hole. The tube was lined with thick botryoidal prehnite and prehnite fingers after anhydrite, up to 6.4 cm, associated with etched calcite rhombs, chalcopyrite and phillipsite. Many hundreds of specimens were removed from this location by Chris and other collectors during a three month period. The best of the prehnite from this locale is unique in New Jersey due to its smooth, glossy surface and bright blue-green color.

6) The world famous Prospect Park Quarry, which ceased blasting in 2011 and is being backfilled for a future housing development, produced copious amounts of prehnite throughout its 100+ year existence. Prehnite was deposited within several structures of the quarry including: 1) diapirs, 2) an amgydaloid and 3) pillow basalt. At Prospect Park numerous dome-shaped diapirs have been identified starting within the lower colonnade of the first flow and extending upward into the overlying entablature. Carpets of prehnite epimorphs after anhydrite line the many openings visible near the upper interior of these structures. An amygdaloidal horizon lies at the top of the lower flow in which prehnite was deposited as thin botryoidal linings. Although the prehnite is average in quality compared to that from other areas of the quarry, the formation of greenockite microcrystals on the prehnite makes it highly desirable. Some of the quarry's finest prehnite comes from the pockets within the pillow basalt located in the second flow at the highest levels of the quarry. Prehnite there has been collected as epimorphs after anhydite, bright green botryoidal linings and isolated spheres in conjunction with zeolites and their associates.

Thanks,
Frank Imbriacco



Edited 2 time(s). Last edit at 12/02/2012 02:45AM by Frank A. Imbriacco III.

The last locality you've presented here, "Augusta Co., Centerville, Quarry", needs to be verified. Augusta Co. is in the Shen. Valley, near Harrisonburg, and includes the mountains to the west. While it does include some Eocene intrusives and volcanics as well as some other Cretaceous(?) igneous rocks like the Buck Hill syenite all these igneous bodies are small and not zeolite-prehnite producers. Even the zeolite mineral assemblage at nearby Sugar Grove, W. Va. doesn't include prehnite. In short, Augusta Co. is not prehnite country.

The confusion may stem from there being several places in Virginia called either "Centerville" or "Centreville", including one in Augusta Co. Your specimens are more likely to have come from Centreville, Fairfax Co. Fairfax Co. includes part of the Culpeper Basin where there are extensive diabase intrusives. Luck Stone has a large quarry in one of these diabase dikes (and in the adjacent hornfels) on Rt. 29 near the Manassas Battlefield.

Frank, Warren,
Thanks for the contribution. Your stuff will eventually be incorporated into the article and will be the stronger for it.

Rock Currier
Crystals not pistols.

Rock

I am somewhat tickled and pleased to see you list prehnite from Coopersburg, Pennsylvania. I once visited the locality back in the early 1980's, with my friend Donald Fluck, who lived in Coopersburg, At the time there was a medium-sized pit, completely flooded to the brime, about 100 by 50 meters in size. Along the western 100 meter length there was a high overhanging cliff. On the level eastern side was a house trailer. The person living in the trailer was familiar with the 'cockscomb' prehnite found at the location, and told us that (of course) the crystals came from vugs located close to the midpoint of the cliff. He offered us the use of his canoe to reach the spot; but, alas, we declined. I had a specimen from here in my collection, very nice, cabinet sized, but this is no longer listed in my inventory, and I cannot now recall what happened to it. May have some pictures, thou.

Jeffrey,
If you have some good pictures of Prehnite from this locality, just upload them to mindat and we will probably add them to the article. Eventually Ill get around to adding some of your remarks about the locality. Any idea what the geology of the place is? Basalt?

Rock Currier
Crystals not pistols.

Rock - Eventually this will happen, all my stuff is in mislabled shipping boxes in the basement, will take some time to sort out, still busy sorting out 2 small-sized and 2 medium-sized children (:P)

Rock,
I collected at Bull Run Quarry Loudoun County,Virginia for a number of years during the 80s and 90s until it was sold to Luck Stone. I found Prehnite over smoky quartz there and as far as I know it is the only occurance in Virginia and the best in the US. There are Mindat photos under my name and reference to my article in Mineral News Vol. No.2 Feb. 2003. This may be a good addition to your prehnite article since it is somewhat an unusual combination for the US and the quality is good. I could get you better photos if you can use them and also any other questions about the location. Thanks for your consideration. Brander Robinson

Brander, Its good enough to include and I did and put in two pictures but better photographs would be preferred. Stop the camera down and take them with a tripod and you will get good sharp images that you can then photoshop, crop etc. What can you tell us about the geology of the place and how much stuff the quarry produced. How many specimens, how many flats? How big the specimens got? How big were the pockets? What do the best specimens from there look like etc.

Rock Currier
Crystals not pistols.

Paul De Bondt

To my knowledge, Prehnite is found only at the La Combe de la Selle.
On Google, la Combe de la Selle gives not hits, even not on Google Earth.
I know that La Selle is a river running through the place. It is not a quarry, that's for sure.
In 1994, while on holydays in the Alps, I visited the Bourg d'Oisans mineral museum but unfortunately, I did not take pictures. I remember some fantastic Quartz pieces and Prehnite and they looked like my specimen, only bigger. My specimen comes from the private collection of the man who found the last big hit of Prehnite, Patrick Allier, before the place became a national park.
From his miraculous find, he kept 3 pieces. Cornered by his divorce, he sold the pieces in 2003 and I was fortunate enough, to buy him that specific one.
I hope to meet him in Ste Marie and will ask. The place and specimens are to important and somebody have to know about it. I will go thru French mineral magazine and I hope to find something.
I keep you informed.
Take care and best regards.
Paul.

Rock Currier
Crystals not pistols.

Hello,

The following should be included:

Vulkan Quarry, Urenkopf Mt., Haslach, Kinzig Valley, Black Forest, Baden-Württemberg, Germany.

It's an abandoned amphibolite quarry, today used as a waste disposal site (dump), no collecting possible any more.

There are clefts in the amphibolite which had apple green, yellow, yellowish brown, colourless to white prehnite. Most of the Prehnite is well crystallized forming tabular xls, but spherical aggregates or balls do occur, too. There are specimen up to fist-size. [I will take a photo the net days] Prehnite from there usually is associated with white calcite and/or white to brownish (beige) pektolite sprays.

As there are no collecting possibilities left, a nice, fist-sized specimen with some Prehnite balls in Germany cost at least 30-50 Euros. There can be found cheaper ones from time to time, but usually those are smaller. Rather rarely on market.

Regards,
Sebastian Möller

Sebastian,Get us some pictures of these and Ill gladly include them in the prehnite article and your comments as well. Can you give us an idea how long the quarry produced specimens and how many specimens were collected? Was the quarry open to collectors more or less continuously? What associated minerals were there? Can you describe one or two of the best specimens?

Rock Currier
Crystals not pistols.

Rock Currier Wrote:
-------------------------------------------------------
> Paul De Bondt
>
> To my knowledge, Prehnite is found only at the La
> Combe de la Selle.
> On Google, la Combe de la Selle gives not hits,
> even not on Google Earth.
> I know that La Selle is a river running through
> the place. It is not a quarry, that's for sure.
> In 1994, while on holydays in the Alps, I visited
> the Bourg d'Oisans mineral museum but
> unfortunately, I did not take pictures. I remember
> some fantastic Quartz pieces and Prehnite and they
> looked like my specimen, only bigger. My specimen
> comes from the private collection of the man who
> found the last big hit of Prehnite, Patrick
> Allier, before the place became a national park.
> From his miraculous find, he kept 3 pieces.

> I hope to meet him in Ste Marie and will ask. The
> place and specimens are to important and somebody
> have to know about it. I will go thru French
> mineral magazine and I hope to find something.
> I keep you informed.
> Take care and best regards.
> Paul.

Hello Rock and Paul,

Very interessant this topic about Prehnite !
Alpine's Prehnite is one of these mineral that i prefer.
I know "Combe de la Selle". In the end of eighty years and the start of ninety years, i colleted some nicies specimens of Prehnite with Patrick.
Congratulations Paul, for your spécimens of Prehnite ! They was found in the best area of field.

Picture 1 : Here is Combe de la Selle prehnitefield in1992
Picture 2 : Prehnite (9 x 7cm) Combe de la Selle 1992
Picture 3 : Here is a location Selle prehnitefield (red cross)

Best regards.
Denis