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Im calling it a sedimentary metamorphic of some type. It looks like the veins are silica rich and a bit more durable than the rest of the rock. That is why the veins "stand up" a little from the surface.

It is mechanically weathered (water/abrasion). That wears more on the softer matrix and the more durable "veins" of silica erode slower. 

Without a good look at the constituent minerals in the "background " rock it will be tough to classify. For me anyway. 

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6 hours ago, PhilanthroPest said:

Any  tesitng i can do from home?   Any chance it is nephrite jade?  So MANY thanks for your help

J.

A hardness  test will give you the most bang for the buck. I wouldn’t bother trying to test the darker areas as those areas appear to be composed of multiple minerals. The lighter areas look like a singular mineral so testing there should get you closer to a correct ID. 


Here’s a link to a site that will get you in the ballpark with stuff you have at home. Once you’ve tested your stone let us know the results and we’ll be able get you closer to an actual ID. I would also suggest a specific gravity test, but being that your stone doesn’t have a singular composition it’s not going to be accurate. 

https://www.oakton.edu/user/4/billtong/eas100lab/hardness.htm

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11 hours ago, PhilanthroPest said:

Any  tesitng i can do from home?   Any chance it is nephrite jade?  So MANY thanks for your help

J.

The green looks like olivine, not jade.

Where did you find it? A location might give us a clue.

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Like Bob said its a metamorphic rock.  I believe the green vain material is the mineral serpentine.

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I weighs noticeably heavier than other rocks of same size.  

I've scratched, hammered meal filed... only the darker rock 'left  a whitish mark  (which is also  a dark green)  Drill bit did noting except scratch darker rock

I see no evidence of crystal... flowing shiny green.veins..darker green does not shine ... I can't find any images of Olivine that resemble this

Found shore of Lake Superior (Canadian side) in a creek bed

Not a Michigan Greenstone... I have lots of that being from Michigan

Too tumbled to check if it will "glow" with a laser light (not even sure that's a 'thing')

NO!  The only gemolgist we have around here is too arrogant to waste my time with... 

Not magnetic

No, I am not breaking it open..  It's too pretty to break,

Hmmmmm!

Are these better clues (?)

THANKS AGAIN ALL!   Super happy to found you!

ps..wait for my next mystery rocks gathered from the Nastapoka Arc area in Hudson's Bay!!!   No one is able to ID this either... 

 

 

J.

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You will never find the mineral olivine in a metamorphic rock.  Olivine is only found in some basalt rocks.

Since you found it in on lake Superior, I can say with certainty that the green material is the mineral serpentine. 

No need to find a Gemologist, this is not a gem.  A very nice sample of serpentine.

O!  Greenstone, is an ancient basalt rock that has been metamorphized.  I believe the Greenstones of Michigan are around 1.8 to 2.5 billion years old.  They represent a time when the North American continent was tearing apart along its, then, western, northern and eastern parts creating what are know as "Flood Basalts".  You can see similar Greenstone in Shenandoah National Park and the Blue Ridge Parkway.  

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4 hours ago, Morlock said:

The green looks like olivine, not jade.

Where did you find it? A location might give us a clue.

Morlock,

I was going to comment about the olivine.... I have never seen Olivine in a flow like that. Only as crystals. And only in deep volcanics and in the Glorieta Pallasites.

It was my assumption that olivine always formed as a crystal under some pretty good pressure. That is just based off my limited experience and nothing else. So im really not sure about that.

 

 

 

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3 hours ago, PhilanthroPest said:

I've scratched, hammered meal filed... only the darker rock 'left  a whitish mark  (which is also  a dark green)  Drill bit did noting except scratch darker rock

 

Well, if a drill bit or a file doesn’t scratch it then it’s far too hard to be serpentine, though if I were going based on appearance alone that’s exactly why I would say it was. At this point I think it’s most likely to be either glaucophane or zoisite.

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You should check the laws in your area. In many locations glaucophane posession is a misdemeanor.

Scratch tests are funky. It depends a lot on the texture of the surface and the shape of the tool that is doing the scratching. It is easy to misinterpret the average backyard scratch test.

I bet a nickel that stone is serpentine. I would call it serpentine. Especially in a location where glaucophane is illegal. 

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3 hours ago, Bedrock Bob said:

You should check the laws in your area. In many locations glaucophane posession is a mistermeaner

May be ,if it was fiberous, and being excavated. But mere possession?

:snapoutofit:

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All that black market glaucophane comes across the border hidden in smugglers underwear. I wouldn't put that stuff in my mouth much less where most users consume it.

Mistermeaner of Felonme doesn't matter. Some minerals are BAD no matter what the law says.

Just say no to bad minerals. :old:

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