Anybody know this rock?

[Beaglejuice13]

I didn't spill my chips and guac....lol. Found in Upper Peninsula of Michigan. Pretty sure it's epidote on basalt with quartz, but what's the black layer? It's not metallic....

 

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[fuss]

Thats not a Basalt rock I don't think, and it looks like calcite instead of quartz. The red part is most likely a K-feldspar. The black is portion is interesting, can you do a scratch test on it?

 

[Beaglejuice13]

Yep, I'll do one today and get back to ya. If not basalt, what about cuprite? Possibly?

 

[Beaglejuice13]

U think epidote is correct for the green part?

 

[stdenis_jd]

looks like a rhyolite that underwent some hydrothermal alteration. You have quartz veins in it and the green is epidote but was plagioclase feldspar that is hydrothermally altered to epidote (as a secondary mineralization probably). I'd have to say the black is an amphibole/hornblende

 

[Clay Diggins]

I'm thinking Olivine instead of Epidote.

It's pretty easy to tell if it's Epidote. In daylight it will look green and in tungsten (old style light bulb) it will appear brown.

 

[Eu_citzen]

Could also be greenish serpentine. See if a knife scratches the green.