This is a large cabochon cut from a piece of Burro Creek Agate - looks like it could actually be Pastelite. It is 136 carats and measures 61 x 41 mm, and 8 mm thick. It is lightly polished on the back as well.
U.S. shipping cost: $6.80
Burro Creek Cabochon Item# 1102 Price: $55.00