Marie
starting to shine!
Member since March 2013
Posts: 40
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Post by Marie on Oct 30, 2013 18:11:10 GMT -5
So I've been trying to identify some green stones, collected locally around coastal southern California. I'm stumped as far as a sure identification goes, and I'm a little concerned that it might be an asbestos. As long as someone here can tell me it's not asbestos, I'll be content! The stones are varying colors of green, from a very pale green to a forest green. The appear like they would be translucent, but most are not. Some of them have glittery specks in them, like the glittery sunstones. Some of them have inclusions of orange-ish streaks and specks, and small black lines that look like mini rutiles. So here's the first photo, where the stones are organized into groups of rough, a grit stage, and polished, going counter clockwise from the top. I had a few pieces tossed in the tumbler with a group with moh's hardness 7 stones, and they polished well. Their hardness is around there, but they may be a bit softer or more brittle than quartz, since the one large polished one got a little "bruised". Here's a close-up of some of the rough pieces. And here's one more picture of the group. Though I have a few hunches, I'm really unsure of what these exactly are. I mainly just want to know that they're safe to handle. I'm sure a more experienced member of the board would have an idea at least. Thanks for looking!
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Fossilman
Cave Dweller
Member since January 2009
Posts: 20,685
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Post by Fossilman on Oct 30, 2013 21:59:58 GMT -5
Alot of California rockhounders on here,I'm sure you will get some info.....
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Sabre52
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Me and my gal, Rosie
Member since August 2005
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Post by Sabre52 on Oct 31, 2013 8:26:17 GMT -5
Looks like metamorphic quartzite which is really common in California as it is metamorphosed from sandstone. Green tones can come from included chromium, chlorite, epidote, iron etc. Some of what you have could just be massive quartz too, which is just an amalgam of interwoven undifferentiated quartz crystals.....Mel
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Marie
starting to shine!
Member since March 2013
Posts: 40
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Post by Marie on Oct 31, 2013 10:21:16 GMT -5
Looks like metamorphic quartzite which is really common in California as it is metamorphosed from sandstone. Green tones can come from included chromium, chlorite, epidote, iron etc. Some of what you have could just be massive quartz too, which is just an amalgam of interwoven undifferentiated quartz crystals.....Mel Yes, I think you're completely right, thank you! I feel silly for not figuring it out on my own. Everything lines up, from location to appearance, even the presence of rutile. I should have figured since it is similar to aventurine, but aventurine does not occur locally. I have some larger pieces, is it any good for cabbing? I have not seen this stuff worked with a lot.
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Deleted
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Member since January 1970
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Post by Deleted on Oct 31, 2013 10:41:39 GMT -5
Maybe I am learning something here. I was under the impression that quartz with shiny specs (mica or schist) is aventurine. That is what I have been calling it here in Wyoming. I have to admit that I am self taught so my lack of real knowledge (like Mel has) on the subject makes me a bit insignificant.
If you have rutilated quartz you have some of the most beautiful cabbing stone on the planet. IMHO Jim
Edited to say that you should not feel at all silly for not figuring it out on you own. We are talking about a HUGE subject here and most of us know very few of the answers and even people like Mel who are a wealth of information get stumped at times.
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Post by Peruano on Oct 31, 2013 17:42:58 GMT -5
I was going to say quartzite as well. It can be polished, but it will never be as pretty as an agate or . That crystal structure of the original sand prevents the transluscent and deep shine of microcrystaline forms of the chalcedony. If you like it, work with it. Some folks will always give it a "B". P.S. I keep picking up reddish rust versions (oxidized iron on the outside where exposed to the elements), but alas am always disappointed it what I do with them. Tom
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Sabre52
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Me and my gal, Rosie
Member since August 2005
Posts: 20,466
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Post by Sabre52 on Oct 31, 2013 20:31:59 GMT -5
Yeah, aventurine quartz is like quartzite with mica inclusions to give it sparkle. It does occur sometimes in the Sierra foothills but is usually aventurine of a sort of peachy tone. I used to find some pretty cool quartzite on the beaches near the Ventura Fairgrounds when I lived in Ojai. Sometimes it has some interesting inclusions. Never found any with rutile but some sure looked like it had chlorite in it and I found one once with little purple cubes that looked like fluorite. Don't know how that formed. Most quartzite can be worked but as Tom said, it can be kind of grainy and not real glassy when polished. Georgia has a really nice variety called Pagan Quartzite that even comes in an almost levi blue color....Mel
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Deleted
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Post by Deleted on Oct 31, 2013 21:46:06 GMT -5
Good quartzite can be REALLY good. We are selling large quartzite slabs for counters and it is better than granite for this purpose. Some I would love to use for lapidary too. Just gorgeous. When polishes they take a real nice polish and have a feel in hand that is out of this world.
I need to learn where I can find local quartzite to play with.
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Post by mohs on Nov 1, 2013 12:16:05 GMT -5
I'd like to go back to the asbestos question I have some great serpentine with fibers, (I assume) is asbestos It shines really great and the white fiber streaks give it chatoyancy effect When grinding the material it creates a grey foamy waxy slurry I'm just working with small pieces of this material I'm not out mining a mountain of serp
How concerned should my lungs be? How concerned should a person wearing serpentine rock'n heart be?
thanks Ed
Not out to hi-jack your fine thread and I think you got some great non-asbestos answers but the question was raised...mostly
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Deleted
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Post by Deleted on Nov 1, 2013 12:52:35 GMT -5
I'd like to go back to the asbestos question I have some great serpentine with fibers, (I assume) is asbestos It shines really great and the white fiber streaks give it chatoyancy effect When grinding the material it creates a grey foamy waxy slurry I'm just working with small pieces of this material I'm not out mining a mountain of serp How concerned should my lungs be? How concerned should a person wearing serpentine rock'n heart be? thanks Ed Not out to hi-jack your fine thread and I think you got some great non-asbestos answers but the question was raised...mostly I dunno Ed. Are you breathing the dust?
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Post by mohs on Nov 1, 2013 13:17:28 GMT -5
I dunnoo neither Scott let me check to see if I'm breathing yep
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Deleted
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Post by Deleted on Nov 7, 2013 17:02:56 GMT -5
asbestos is only an issue when you breathe dry dust at a certain specific particle size. Wet grind wear a mask?
I'd do it myself.
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