Agate is one of the most varied and desired forms of chalcedony which is one of the many varieties of quartz.

Banded Agate

Moss Agate

Quartz is the single most abundant mineral on earth, making up almost 12% of the earth’s crust.  Quartz varieties are separated into two basic groups, macrocrystalline and microcrystalline.

In macrocrystalline quartz the individual quartz crystals can be seen with the naked eye.  In microcrystalline, sometimes called cryptocrystalline, the individual crystals are too small to be seen unless microscopically viewed using polarized light.

Agate is scientifically classified as a cryptocystalline quartz.

Agate was given its name by Theophrastus, a Greek philosopher, who discovered the stone along the river Achates in Sicily around the 3rd or 4th centuries BC.

In ancient times it was believed that Agate protected the wearer from danger and promoted healing and strength.