From the same chalcedony family as agate, onyx often also displays bands of alternate light and dark material. Stones are usually black or black and white, although jewellers tend to clarify these as ‘black onyx’ as other varieties do exist. Sardonyx, for example, is the name used for brown and white banded onyx. The colour contrast is widely exploited in carved ornaments or cameos, as the layers can be used to differentiate between the design and the background. In jewellery the dense black stones are particularly set off by sterling silver or other white metals.
Did you know?
- Onyx is one of the 12 stones mentioned in the Bible as having adorned the high priest’s breastplate.
- Onyx jewellery is often given to celebrate a 7th or 10th wedding anniversary.
- The name comes from the Greek onux meaning nail or claw, possibly relating to the legend that Eros cut Aphrodite’s nails while she was sleeping, scattering the clippings which turned into onyx stones.
- Brazil and Uruguay are rich sources of onyx, with mines also found in India.