Spider jasper from Mexico is a reddish brown gemstone with crystals in star or spider patterns throughout the material. (Stock 380) Sizes of the rough spider jasper will range from 1/2 to 10 pounds plus. This distinctive material has made some very nice interesting cabochons using diamond grinding wheels. With the hardness variation in the material, diamond grinding works the best for polishing. It will not take a polish in a tumbler. Check below for more samples of spider jasper from Mexico.