Soft, fragile, and hard to cut, celestite or celestine is seldom seen in gem collections. Large, clean faceted celestites are very rare. These gems are usually colorless or pale blue, but rare orange, green, yellow, and red shades have also been found.
Start an IGS Membership today for full access to our price guide (updated monthly).
Celestite gems, usually colorless or pale blue, typically weigh under three carats and often receive step cuts. However, some gems are known in the 30-carat range. Large, transparent crystals may be found and cut.
Put-in-Bay, Ohio boasts the Crystal Cave, “the world’s largest geode.” Converted into a cave, the 35′ wide geode contains celestite crystals up to 18” across.
Devonian Group (Calgary, Alberta, Canada): 20.1 cts (blue, Madagascar).
National Museums of Canada (Ottawa, Ontario): 3.11 cts (orange step cut, Ontario, Canada).
Due to its softness, perfect cleavage, and light sensitivity, this gem makes a better collector’s item than a jewelry piece. Celestites also have great heat sensitivity. Since jeweler’s torches can easily exceed 200° C (392° F) and cause the stone’s colors to fade, be wary if you take a jewelry piece to be repaired. Consult our gemstone jewelry cleaning guide for more recommendations.