Brown jade?

pure white jade hidden deep inside a boulder with a thick brown rind

There was a time not so long ago when the thick brown rind on white jade boulders found in Siberia and the Kunlun Mountains was discarded as not worth carving. This has changed in recent years. You can now find pendants, rings and necklaces carved from the rind itself. (This recent innovation is not to be confused with the way the rind of jade pebbles found in the White and Black Jade Rivers in Hetian (Hotan) is used by master carvers. That is a different skill on another level altogether.) Learn more about jade at www.jadefiend.com

A small tablet fashioned from the rind of a boulder of white jade