Sardonyx

My Jeweler

Jewelry 101--Colored Stones

Sardonyx

The most ancient of the August birthstones, sardonyx has a rich history and is actually a combination of two other gemstones, sard and onyx, both of which are types of microcrystalline quartz called chalcedony. Sardonyx has alternating bands of brownish red or yellow sard and white or black onyx. These bands make sardonyx an excellent choice for carving cameos and intaglios. In ancient times sardonyx was a popular stone for Roman seals and signet rings because hot wax would not stick to it. Believed to protect them in battle, Roman solders wore sardonyx rings with the image of Mars carved on them. Today sardonyx is associated with courage, happiness and clear communication, bringing stability to marriage and partnerships.

This gem is a combination of two types of chalcedony (microcrystalline quartz), sard and onyx.
The alternating bands of brownish red to brown to dark orange sard and white or black layers of onyx, make this stone popular carving material for cameos and intaglios.
Sardonyx, like onyx, shows layers of parallel bands—instead of the chaotic, curved bands that compose agate, another type of chalcedony.
Sardonyx has been popular for centuries, dating back more than 4,000 years ago to the Second Dynasty of Egypt.
Sardonyx was a popular stone for Roman seals and signet rings that were used to imprint wax emblems on official documents—due to the fact that hot wax doesn’t stick to this gemstone.
Unlike rare gemstones that were historically limited to wealthy royals, sardonyx has been popular with elite and regular folk alike. Relatively common and inexpensive, sardonyx is a beautiful gemstone that’s affordable enough to join any collection.
Sardonyx is the most ancient of the August birthstones.

Specs

Chemical Formula	SiO₂	Mineral Class	Quartz (Chalcedony)
Color	Banded white or black and orange
Crystal System	Hexagonal	Hardness	6.5-7
Transparency	Translucent to opaque	Luster	Vitreous to waxy
Refractory Index	1.544 - 1.553	Double Refraction	0.009

Legends

Sardonyx is believed to be one of the stones in the High Priest’s breastplate, as referred to in the Old Testament, and to represent the strength of spiritual life.

Roman soldiers wore sardonyx rings with the image of Mars carved on them for protection in battle.

Today, this gemstone is associated with courage, happiness and clear communication, bringing stability to marriage and partnerships.

Used as a stone of strength and protection in ancient times, sardonyx is associated with courage, happiness, and clear communication.

Ancients believed that placing a sardonyx gemstone at each corner of a house will grant protection against evil.

Ancient Greeks and Romans went to battle wearing sardonyx talismans engraved with images of heroes and gods like Hercules and Mars. They believed the stone could harness the bravery of those figures, granting them courage, victory and protection on the battlefield.

During Renaissance times, sardonyx was associated with eloquence. Public speakers and orators wore it to aid clear thinking and communication.

In Ancient Rome, women wore sardonyx necklaces with cameos of Venus in hopes of harnessing the power of the goddess of love.

Sardonyx was also a popular stone for Roman seals and signet rings that were used to imprint wax emblems on official documents because hot wax doesn't stick to this stone.

Used as a stone of strength and protection since ancient times, sardonyx is associated with courage, happiness and clear communication. It brings lasting happiness and stability to marriage and partnerships.