I was breaking away some calcite when an unusual glimmer caught my attention.
I've run a few tests. It tarnishes black under oxidizing flame and does not emit a color. I cannot hold a sample well enough with any of my tools to get a scratch or streak test done.
http://imgur.com/a/PAHgz - a couple of pictures of the material, freed from the calcite matrix in which it was found.
It's dense. Water puffing easily moved dense garnet sand away from it while it remained relatively still.
The measurements taken on one sample grain were as follows: ~0.7mm length, ~0.7mm width, ~0.5mm thickness. Multimeter resistance measured at 35 Ohms. This gives me an electrical resistivity of 0.025 ohm meter, or 2.5 x 10^-2. I cannot find any metal with such listed electrical resistivity. My best bet would be that this is a semiconductor, given the relatively high resistivity, as pretty much every metal starts at 10^-6 to 10^-8.