Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
Lydian stone, or black jasper, a variety of siliceous or flintyslate, of a grayish or bluish black color. It is employed to test thepurity of gold, the amount of alloy being indicated by the color lefton the stone when rubbed by the metal.
Share your knowledge with the community
Browse our collection of 300,000+ community-written definitions
