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Sard is a brownish mineral, and when it forms together with the straight white bands of onyx, the resulting stone is called Sardonyx. Sardonyx is a banded variety of chalcedony which is cryptocrystalline quartz. Some Sardonyx is natural but much is produced by the staining of Agate.


Sardonyx protects against plague and the bites and stings of poisonous reptiles and insects.Stimulates self-control and protection. Ensures a happy marriage. It is used for protection, courage, peace and luck and it promotes happy conclusions in legal and contractual agreements.

Physical Properties:


Sardonyx  Birthstone

Blue, Blue Lace, Moss, Pink, Red
Specific Gravity
2.65 - 2.66
Refractive Index
1.543 - 1.554

Sign of Sardonyx: Leo


Sardonyx was very popular and highly valued in antiquity. Roman soldiers often wore Sardonyx stones engraved with Mars, the God of War, to render them brave and fearlessness in battle. It was a favorite gem of the ancients and many thousands of years ago the Egyptians engraved these gems as scarabs and beetles and wore them as talismans.


India. Other sources include Germany, the Czech Republic, Sri Lanka, Brazil, and the United States (Oregon and the Great Lakes Region).