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Identity HelpU.P. MICHIGAN- RAW Chlorastrolite/ Michigan Greenstone?!?

13th Jul 2021 23:43 UTCLuxe_ Sapphire

I need help identifying this please. I was born and raised in the U.P. But currently live in Texas. I visited recently and was given this last time I went up there to visit and told of its rarity. It was labeled as U.P. Chlorastrolite.
After researching I’m convinced it’s Chlorastrolite. I also read that Chlorastrolite goes for $40,000 per pound. Is this true?

There is a video below

TIA

14th Jul 2021 00:00 UTCLuxe_ Sapphire

More pics

14th Jul 2021 00:05 UTCLuxe_ Sapphire

And some more pics

14th Jul 2021 00:06 UTCLuxe_ Sapphire

One more!

14th Jul 2021 00:01 UTCLuxe_ Sapphire

Pics of the crystals

14th Jul 2021 00:01 UTCLuxe_ Sapphire

Actual pic of identified Chlorastrolite for reference to mine. They look exactly the same. What do y’all think?

14th Jul 2021 00:33 UTCRobert Nowakowski

There is chlorastrolite in your rock but only in the tiny pockets scattered throughout. Chlorastrolite is a variety of the species pumpellyite and the entire Keweenaw Peninsula is underlain by your rock type. So although we do not provide valuations on mindat, your rock has little value monetarily. But value is not why we all collect minerals fossils and rocks.

14th Jul 2021 00:42 UTCLuxe_ Sapphire

Thank you for your response. That makes perfect sense and what I wanted to know. It was labeled “Chlorastrolite” and not for sale because of its value but it was given to me since I was friends with the owner. I’m not sure why he would label it as rare U.P.

Chlorastrolite then? Thanks again!!!

14th Jul 2021 00:46 UTCLuxe_ Sapphire

Could you look at the video I posted below? Is there a way to expose the greenstone a little more?

14th Jul 2021 00:51 UTCLuxe_ Sapphire

So this type of specimen is abundant through out keweenaw? And yes I know that’s the only place to find this and there was a transform boundary going through the U.P. About 1 billion years ago which produced volcanoes and lava- creating pumpelyite and whatever is left is what we have! I understand all of that but I guess I didn’t realize my rock is all over in Keweenaw! Interesting! Thx!

14th Jul 2021 01:05 UTCRobert Nowakowski

You should search pumpellyite on mindat. Pretty common in volcanic rocks throughout the world. But when found in compact masses that can be polished, as chlorastrolite, it is not nearly so common.

14th Jul 2021 00:09 UTCMark Heintzelman 🌟 Expert

I see no resemblance to your rock and "Chlorastrolite" i.e. Pumpellyite (Mg) from Michigan.

Yes, "greenstone" has a good deal of value depending on its visual qualities once it's been fashioned into an ornamental stone for use in jewelry, but see no inclusions in your rock that might be fashioned into such a stone.

14th Jul 2021 00:31 UTCLuxe_ Sapphire

Did you look at the example? It looks exactly the same.

https://share.icloud.com/photos/0cT1NKJe8wKcQg-hN7RPSgcSQ

14th Jul 2021 00:38 UTCLuxe_ Sapphire

This was displayed at a business. They werent selling fake rocks. This was not for sale but it was labeled and shown as being rare and it was given to me by the owner who I am good friends with. The tag said Chlorastrolite, I went back and checked on the website. Why are you putting “Chlorastrolite” into quotations like I’m saying it wrong? I’m aware it’s a Pumpellyte (Mg) as well. Thx for the info

Here is another example, it looks EXACTLY like these? Above they said it’s a lower quality and more abundant.

14th Jul 2021 00:47 UTCPaul Brandes 🌟 Manager

Welcome to Mindat, Luxe.

First, let me start by saying that we do not give values on specimens here.

Regarding your specimen; other than maybe a few spots on the third photo, I see very little evidence of chlorastrolite. Also, please note that not all green spots on basalt are chlorastrolite as many are just chlorite which can look very similar. I wouldn't actually say they are that rare, and if one knows where to look you can find quite a few in an afternoon. What is rare are the large ones in Mark's post; those are indeed hard to find these days...

14th Jul 2021 01:44 UTCHerwig Pelckmans

Here is more info on this material:

https://www.mindat.org/a/chlorastrolite

Cheers, Herwig

14th Jul 2021 18:56 UTCLuxe_ Sapphire

So I wonder if I should split this open and see if there’s anything inside?

14th Jul 2021 21:15 UTCDave Harmon

I would say you have nothing to loose breaking it open. You MIGHT find a nodule.

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