Spiderwoman slabs come from Oregon near the Idaho border. It is a fine-grained basalt rock composing of at least 65% feldspar. The Moh’s hardness is 6 to 6-1/2 and it cuts easily. This material polishes with cerium, diamond or tin oxide. Spider Woman contains fine red lines creating a web effect that can be very striking.
Ruler is in INCHES.
Example of Spiderwoman Cabochon
Note: Not cut from material below.