Gabbro Beads (2)

Gabbro, a coarse-grained, intrusive igneous rock is the most abundant gemstone material in the deep oceanic crust.  Gabbro is composed mainly of calcium-rich plagioclase feldspar (usually Labradorite or Bytownite), Pyroxenes (usually Augite), and Olivine might also be present. This mineral composition usually gives gabbro a black to very dark green color. A minor amount of light-colored mineral grains may also be present in this beautiful gemstone from the deep ocean.