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Identity HelpHello Again! I need help identifying specimens recently given to me
12th Jun 2018 00:46 UTCBecky Elizabeth
I recently acquired a shoebox from the 1930'3-40's that had been sitting in a science teachers closet for decades untouched. He was going to through the "rocks" away and my stepfather mentioned that I'm beginning to study and he brought them home. There aren't many clues folks except there was an obvious Smokey quartz twin crystal, 2 glass jars, each with labels: the 1st "mica sheets" and the other "limestone".
There are some old note cards that say "items used to make steel" and an antique prescription bottle that seems to be marked "fluorospars?" with some clear, yellow calcite shards etc.
There is masking tape that was on petrified wood and then a very large piece that says "obsidian" but I've only seen obsidian in small form. If I can't post all pics here I'll add them in comment section And start with the one labeled yellow obsidian but it's red brown. Thanks again, Becky Elizabeth
12th Jun 2018 01:38 UTCAlfredo Petrov Manager
12th Jun 2018 01:49 UTCBob Harman
I wasn't sure from your 2 postings whether the 3 pix in each post were different views of 2 rocks or all represented different examples.
I will assume that the 3 px in each posting were 3 different views of 2 rocks.
It seems clear to me that these were picked up at or near the roadside of his trips thru different national parks in different states.
The first one is probably obsidian from the roadside thru Yellowstone NP. The 3rd picture shows some chonchiodal fracture suggesting the obsidian, but the other 2 pix are not conclusive.
The second series of 3 pix seems to show a coarse grained granite, as part of the Appalachian mountains, picked up in the Great Smokies NP in 1971, probably in a Tennessee site.
While the rocks have great personal and sedimental value to you, neither has any other consequence.
That is my take on your pictures. CHEERS......BOB
12th Jun 2018 04:48 UTCBecky Elizabeth
12th Jun 2018 04:53 UTCBecky Elizabeth
Also, pardon my ignorance, but what is the difference in "obsidian found by the road in Yellowstone" compared to all of the various tumbled and natural smaller pieces I have in my collection?
12th Jun 2018 05:38 UTCMatt Neuzil Expert
Looking at the 1971 rock to me it says Copper, (something I cant make out) and M.T. MT would be montana? But I agree it at least look granitic and the label has been smeared.
12th Jun 2018 06:00 UTCBecky Elizabeth
12th Jun 2018 06:02 UTCBecky Elizabeth
12th Jun 2018 20:38 UTCJohn Oostenryk
Can solve some of these for you.... Here's a quick review starting at bottom of your pics.
The bottom is a piece of rhyolite with jelly/fire opal. Mexican origin.
pill bottle--
white qtz chunk--chunk of (massive material) (not meaning size, but that's a geology definition, uniform composition, formless, no structure.)) (old term was also 'bull qtz' meaning milk white massive, thick and stubborn while mining.
purple fluorite - mined as ore, it is called 'fluorspar'. Calcite mined as ore was called 'spar' Those might originate from the German language??
Looks like two other bits are from fluorspar tailings- have some color too?
wet grey/black granular chunk. ?? I'm 'guessing' but may be super fractured piece of quartz from a pegmatite (hence bigger but crackled) you can call it smokey qtz. Again a 'massive' type piece.
do physical tests to verify this one.
grey and white chunk-- too much flare/glare on first word on tape- but it also says "Smokey Mts" which is central East Coast USA. Typical for igneus/metamorphic rocks. white quartz (qtz) or maybe a marble (acid test!) with grey something~ maybe a gneiss? or just clay/micaceous veining during folding or intrusive cracking and fuid fill (OR both) ?? :)-
Obsidian? The note is clear~
It looks like chalcedony or obsidian- with the tannin staining from organics, accumulated during near surface burial.
FIRST--DO make a small neat copy on paper, then peel tape off with a razor blade, (save or pitch~) I am not fond of crumbly tape crumbs or goo- so I pitch.
I'd consider it may have been a core from a pre- euro contact~ human tool making project. OR OR, they do spall like that being eroded and stream transported (banging along in flash flood!) No big deal~ tis just a rock with a tad more interesting details than most.
including the pick up during original development of Yellowsstone. That IS neat lil detail- hence 'keep a note of note'.
SECOND--Give it a hot tapwater dishsoapey soak with good dollop of straight bleach, (Knocks off the organics in 30 min?) Soaking time longer won't hurt it, so at your convenience...
Pour off soak fully. Then a good rinse or three (dont splash ya clothes!!! bleach splatter will wreck them! How do I know :( )
THEN good scrub while wet with a brush. (you are avoidiing the brush splatter issue with bleach by bunch o rinsing ;)-
Third-maybe- if the tape leaves stickey residue- wet a bit of cloth or paper with WD-40 (the spraylube etc product.) with wet spot- rub! should pretty rapidly come off, repeat for effect. If stubborn, dab enough on the residue so it is wetted, let sit 10 min or so, then rub.
The WD works great on any [label/tape adhesive*] I have seen yet- and not issues with 'melting' plastic like other solvents I have tried... Some times the older dried on crap does take several wetting repeats before it softens up- then it comes off easy enough!
(oh- and I do mean label-tape adhesive~ not 'glue'!
glued repairs- THOSE are all worked by acetone. DIFFERENT type project ;)- and it DOES eat plastic! (never rocks)
EXCEPT modern 'hot gluegun stick'-- isopropyl alcohol is releaser~
With it clean as may be- its either chalcedony or obsidian!
Have to look at those edges and nicks for translucency and grain texture, inclusions, while bright back lit...
Honestly, I am betting 50/50.
It may turn out as a piece of chalcedony that is either black/brown petrified wood or pet wood 'limb cast' complete replacement by chalcedony. (Often called Montana moss agate- which comes down the Yellowstone River into MT from Yellowstone...
Most often that chalcedony is blackblack or deep grey to black, with NO manganese etc dendrite inclusions (moss) ...
They often are 'cobble' shaped by formation and further erosion transport. Obsidian can do the same during stream transport.
Ok- I went a little long but is fun!
Report back on that cobble!
Cheers!
~JO:)
12th Jun 2018 21:29 UTCBecky Elizabeth
Thanks for the cleaning notes. Honestly I did a lot of reading but it was more crystal specific I guess because I soaked and used a brush on all of them for hours but didn't use any bleach. Think back to my bio chem college days (well...organic to be specific about oh and cleaning) but that makes perfect sense!
12th Jun 2018 21:31 UTCBecky Elizabeth
These are what I thought had to be the petrified wood specimen.
13th Jun 2018 02:30 UTCDoug Daniels
13th Jun 2018 13:11 UTCEd Clopton 🌟 Expert
13th Jun 2018 15:02 UTCBecky Elizabeth
13th Jun 2018 19:27 UTCJohn Oostenryk
OR- maybe they picked it from the 'tailings' at a copper location because of the color contrast (black/white) and it has NO copper content! I see THAT, a LOT in the MISC stuff from "old collections"!
Hence the HUGEEE reason to always have some info attached to the random stuff in your collection...
But, there is also the issue where you are passed on~ or the "stuff" is passed on, and the info went elsewhere. Argh! :)-
And the Last 3 pics- Doug D above should say- It didn't look like pet wood to him. No offense!
YES- all three of those are pcs of pet wood!
Not killer pieces and thus quick pics can't help that, but not lost ;)-
Top one is a spall. (silica replacement = chonchoidal fracture = chunk). The wood grain is not well preserved but I can see it.
Middle is a saw cut face. Again- wood structure diverging in two directions at least. Pic is not great for ID
Bottom- certainly a wind or water polished piece of pet wood!
There ya go!
~JO:)
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Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 27, 2024 01:01:01