Significados de black mica en inglés

Granite.-Colourgrey; feldspar, black mica, and quartz: succeeds the sandstone, and continues to the S.W.

The quartz diorites are: some medium-grained, some coarse-grained (quartz-diorite-pegmatite), with streaks of black mica.

Geologists spent a week removing a thick layer of black mica from the rock before finding 127 medium green emeralds.

It is a granite passing into gneiss, and remarkable for the peculiar distribution of the black mica, which forms little ramified veins.

This is a white feldspathic granite, with small scales of black mica; smoky quartz and garnets appear to constitute this portion of the mountain.