Hope this is Really Muscovite

I bought this particularly lovely stone at a local bead wholesale shop and it was labeled "muscavite" which actually is a native from Muscovy, an ancient region in Russia (probably where the name "Moscow" comes from). There is a mineral called muscovite (with the letter o, not a) but almost every picture I pulled up showed a pinkish red stone, with somewhat of a schiller effect.

So I have a dilemma as to what to put on the label for this piece, which is now completed. Perhaps it's the metallic flecks on the stone that is the "muscavite" although it looks more like pyrite to me than mica. If that is the case, I would love to know what to call the resident stone since it is the majority of the composition.

Is it a granite? A basalt? A gneiss?? It is beautiful, especially in person. The color is a deep charcoal with a slight hint of green. It looks like biotite, except it doesn't easily break into sheets like typical mica.

I'm stumped. Any rockhounds or petrologists visiting here, please weigh in what you think this may be.

In the mean time I will have to come up with something creative for the tag. At the moment, it only has the $72 price on it. I used 14k gold-fill wire for both the wrapping and the linking of the beads. I used 8mm Swarovski crystals, black diamond color, and the combination is stunning. I'll put up a picture of the completed necklace as soon as I get to photographing it.