All cabs or blanks are approximately 1/8" thick, polished to a glassy finish and ready for scrimshaw. Prices shown are for creamy mammoth, if you require dark fossil ivories please inquire, we have gem grade that is too dark/colorful for scrimshaw but spectacular for jewelry as is. We do custom cabochon cutting, so if you need a particular size/shape not seen, please inquire. All cab and blank sizes are given in millimeters; 25mm equals an inch.