electricface
starting to spend too much on rocks
First fish of the day
Member since August 2012
Posts: 211
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Post by electricface on Feb 26, 2013 23:03:56 GMT -5
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Post by jakesrocks on Feb 26, 2013 23:16:31 GMT -5
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Post by NatureNut on Feb 27, 2013 8:54:37 GMT -5
Actinolite
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Post by Bluesky78987 on Feb 27, 2013 15:02:53 GMT -5
Yup, Fuchsite.
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Minnesota Daniel
freely admits to licking rocks
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Post by Minnesota Daniel on Feb 27, 2013 17:49:17 GMT -5
I'm going to disagree. I've shopped at the Rock Shed for several years now, and I've bought small mixed rock from them too. Given the source, I think it's more likely you've got a piece of green aventurine. Although the name is often misused, aventurine is not just colored quartzite, it's mainly quartz with feldspar and importantly, mica. Sometimes it can be very flakey and glittery. I remember small pieces of that quality of green aventurine in the mixed rock I bought. I have a chunk of red aventurine now, and the outside of it is too flakey and sparkly to use, but the center is hard and translucent and displays nice aventurescence. The Rock Shed sells green aventurine. That's a piece of the soft flakey stuff that ends up at the bottom of a shipment of the tumbling rough they buy. That's what their mixed bags are -- the broken pieces at the bottoms of the barrels of all the stuff they sell.
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electricface
starting to spend too much on rocks
First fish of the day
Member since August 2012
Posts: 211
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Post by electricface on Feb 27, 2013 23:33:24 GMT -5
so given the source location(therockshed) green aventurine? or fuchsite? or Actinolite? I don't know. It looks like fuchsite but the from your experience Daniel I'm thinking you probably got it. Anyone else want to weigh in? It is obviously not tumbleable, and it looks really cool. I just need to know for sure what I got so I can label it.
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Post by jakesrocks on Feb 28, 2013 0:14:18 GMT -5
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Minnesota Daniel
freely admits to licking rocks
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Post by Minnesota Daniel on Feb 28, 2013 0:25:16 GMT -5
This is aventurine: If I run my hand over it the flakes come off like mica. If it was green it would look pretty much the same as the stuff in question. It's a metamorphic blend containing quartz and mica. What I think you have is the rotten stuff that sometimes accompanies a sold junk of rough. The same rock cut: The top surface will wear off right away, but it will certainly polish. The tiny white specks - kinda hard to see before it's polished - are the aventurescence. Lots of stuff sold under the name aventurine is just quartzite. Most of those pictures of "aventurine" are only quartzite. Only a few pics with sparkly aventuresence are true aventurine.
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jamesp
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Post by jamesp on Feb 28, 2013 7:29:54 GMT -5
Wikopedia will help clarify.It claims there i aventurine and aventurine felspar.It says confusion occurs in the felspar issue.It happened to me a few days ago when Snuffy posted some tumbled yellow aventurine and i thought it had felspar in it and he said it was quartz.So i looked it up and got a Wikopedia def.With a mohs hardness of 6.5 it pollutes my opinion of it being quartz,maybe because it is quartzite quartz.Seems to be a bit of a generic word also.I see orange,yellow and red felspars;they are apparently Sunstone often confused with aventurine like i did w/Snuffy's yellow aventurine.Aventurine's definition says it has plate like mineral inclusions(mica?). I would tumble that in a second Tony.It has plenty of quartz in it to take a polish.It fractures on the mica making it look like it has more mica than it really does.And it will glitter like there is no tomorrow. Hell,i live in Georgia where about every rock is mica,quartz and felspar=granite.And the granite that tumbles with lots of sparkle is the ones overdosed with mica.Tumble that sucker:> en.wikipedia.org/wiki/Aventurine
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Post by helens on Feb 28, 2013 10:21:32 GMT -5
I'm inclined to agree with aventurine by looking at it too... aventurine is used to color glass, because of the shiny bits, so I've worked it before, and have it blended with glass frit (works like crap in glass because it burns off so easily).
If you look at the pix, actinolite has long thread-like crystaline structures (like kayanite), while the aventurine is more flakes and small chunks all mushed together, even though they are similar looking colors and textures.
I don't think it's fuschite because you didn't mention it was super soft. I ground a piece of fuchsite and the stuff sort of vanished under the wheel. With a hardness of 2-3, where the average human fingernail is around 2.5, you can scratch fuschite with your fingernails if you have healthy strong nails, and if not, any piece of glass would scratch it (glass is 5.5 hardness). The stuff is SOFT.
Is it SUPER soft? If so, it's fuchsite.
Does it have long crystal forms laid out in threads (like kayanite)? If so it's actinolite.
Does it have short crystal forms and is relatively hard? If so it's aventurine.
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Post by rockpickerforever on Feb 28, 2013 10:28:24 GMT -5
It appears to have the same structure as Lepidolite (Potassium lithium aluminum silicate hydroxide fluoride), an ore of Lithium. It is normally violet to pale pink or white and rarely gray or yellow. But I have seen some green varieties of it. Despite its hardness of only 2.5, I have seen it take a good polish. Jean
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Post by Hard Rock Cafe on Feb 28, 2013 13:18:42 GMT -5
Funny, Jean, I also thought lepidolite, but I've never seen it that green. There is a lepidolite deposit near Mt. Rushmore, just south of Keystone (where The Rock Shed is located). That is obviously not a definitive answer, as it could very well be any of the others mentioned.
Chuck
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Minnesota Daniel
freely admits to licking rocks
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Post by Minnesota Daniel on Feb 28, 2013 14:34:14 GMT -5
Wikipedia is notorious for repeating "common knowledge" without questioning it. Google the term and the results are quite likely to proliferate the confusion. Ever notice how many times you find definitions and explanations on the internet that are word for word identical? That's plagiarism, not additional confirmation of the answer.
I think the term aventurine is partly a case of "industry" using a misleading description until it becomes an accepted term. Aventurine sounds more impressive than green quartzite. Smokey topaz sounds better than smokey quartz too. Why would they name the characteristic of aventurescence after a rock that didn't even display it? Also, in good faith, sources are probably selling "aventurine" without any aventurescence at all when it comes from the same place the aventurescent aventurine is mined. When you see green quartzite for sale, it probably comes from a source that isn't associated with mica.
Feldspar aventurine is a somewhat misleading term for sunstone, a feldpar that contains specks of iron oxide that sparkle. It displays aventurescence, but it's not aventurine. Not every rock that displays labradorescence is labradorite either.
I have never seen the Rock Shed sell online, fuschite, much less actinolite, but I've never been there in person. They do however carry apatite. I'm not personally familiar with that rock, but I think it might be somewhat similar to what you have. As Chuck alludes to, this might well be a piece of something local that they aren't able to get enough of to sell online.
Why don't you drop Shawn (at the Rock Shed) an email (with pic attached) and ask him what it is? It takes the fun out of trying to figure out what it is, but you'll undoubtedly get the definitive answer.
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Post by helens on Feb 28, 2013 14:34:17 GMT -5
Well... how soft is the green stuff you got, Tony:)?
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Post by jakesrocks on Feb 28, 2013 15:37:38 GMT -5
For those who don't know what green aventurine looks like in the rough, I just took this pic from my private stash. You can clearly see the flashes of silver mica in the quartz matrix. The Matrix is Mohs 7. The mica obviously is much softer.
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Minnesota Daniel
freely admits to licking rocks
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Post by Minnesota Daniel on Feb 28, 2013 17:49:38 GMT -5
Thanks for the good picture Don. Almost all the green aventurine I've seen personally has been real aventurine. I've often picked through bins of it and found junks of what I call the rotten stuff - more mica than quartz. I've seen it between good layers of rock too. It usually separates there.
I've never seen yellow or peach aventurine though that I'd call anything but quartzite. I've tumbled it too. I read somewhere, probably here, that the Chinese are dying quartzite and calling it aventurine. In jewelry I have seen suspicious looking "extreme green" aventurine lacking any aventurescence. I'm sure they're trying to make it look like fine jade.
I was always suspicious of "raspberry aventurine" until I acquired the piece I have. It's layers are so metamorphosed that they are crumpled, and disappear altogether in the middle of the rock. There it looks pretty much like you'd expect quartzite to look, except for all the sparkling aventurescence. The source was directly from the mine in Southern Ontario, can't recall exactly where. You don't ever want to pay shipping from Canada if you can help it.
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electricface
starting to spend too much on rocks
First fish of the day
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Post by electricface on Feb 28, 2013 19:46:36 GMT -5
Well the green stuff is not all that soft. Cant scratch it with finger nail. It does scratch with a knife however. I don't have a piece of glass available. There are spots on them that is solid instead of having the flaky look. I'm going to send Shaun a pic and see what he says about it. I'll let everyone know what he says.
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electricface
starting to spend too much on rocks
First fish of the day
Member since August 2012
Posts: 211
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Post by electricface on Mar 1, 2013 11:49:43 GMT -5
Well fellow rock enthusiast the answer has come down from the source. Shawn confirms it as Fuchsite. He says the people who bag his rough for him are supposed to pick it all out but every once in a while some slips by. Thank you everyone for your input. And thanks for the idea to send a message to Shawn. It shall be labeled and place in a spot of interest. Thanks again.
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Post by jakesrocks on Mar 1, 2013 12:04:55 GMT -5
Glad you finally got a positive ID. Even if it's too soft to cab, it will make a very nice specimen for the cabinet.
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Minnesota Daniel
freely admits to licking rocks
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Member since August 2011
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Post by Minnesota Daniel on Mar 1, 2013 15:06:07 GMT -5
Well fellow rock enthusiast the answer has come down from the source. Shawn confirms it as Fuchsite. He says the people who bag his rough for him are supposed to pick it all out but every once in a while some slips by. Thank you everyone for your input. And thanks for the idea to send a message to Shawn. It shall be labeled and place in a spot of interest. Thanks again. And now we know the rest of the story. I should have suggested you call Shawn before I went off on a tangent about aventurine. Misleading names in the rock and gem hobby/industry bug me. I think it's important to know what it really is when we buy, cut, tumble and cab stones. Especially when it effects the price. I suppose it didn't make that much difference in your situation, but I'm glad you now know what it is. I should probably apologize in advance for going off on the difference between moonstone and rainbow moonstone. I'm sure that will happen some day. (sheepish grin)
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