SARDONYX, a variety of agate with alternating orange and white bands
- VARIETY OF: Crypto-crystalline
- USES: Gemstone and ornamental stone.
- COLOR: alternating bands of yellow-brown and white
- HARDNESS: 7
- CLEAVAGE: none
- CRYSTAL SYSTEM: none visible (actual crystals are microscopic)
- For natural Sardonyx mineral specimens see our For Sale or Sold lists
Sardonyx is a banded variety of
chalcedony (cryptocrystalline quartz),
with layers alternating between Sard
and Onyx. It is an impure fine-grained quartz whose crystals are
too small to see.
The color is usually a yellow-brown alternating with white, but other variants
are also called sardonyx.
The banded nature of sardonyx is used to advantage by lapidaries and artisans,
as a careful selection of material and design allows the creation of bas-relief
art, where one layer is left as a foreground, and another is used as the
background for a carving.
Sardonyx is the traditional birthstone
for August. It is associated with relaxation and security.
Sardonyx is only one of several
chalcedony (cryptocrystalline quartz) varieties.
The primary varieties are as follows:
- Agate is a banded variety
(sometimes with translucent bands)
- Bloodstone is
green with red speckles
- Carnelian is yellow
- Chrysoprase is
- Flint is generally black
with a fibrous microscopic structure
- Jasper is any colorful
- Onyx is black, white, or
alternating black and white
- Sard is yellow to brown
- Sardonyx is banded,
alternating sard and (usually white) onyx