This Carnelian Palmstone is approximately 51 x 56 mm; thickness is approximately 31 mm, weight is approximately 127 grams. Please note these will be a random pull (unless you can communicate with us a specific one on the photos) and the above measurement(s) are average at best. 
 
Carnelian is a red/orange (fall colors) crystal that is a variety of Chalcedony. The color comes from Iron Oxide. The finest of the Carnelians can be found in India, however it can be found in Brazil and Madagascar as well. Has a Mohs of 7.