Agate, which is also Chalcedony is known by many forms. No gemstone is more creatively colored and striped by nature than agate, chalcedony quartz that forms in concentric layers in a wide variety of colors and textures. Each individual agate forms by filling a cavity in host rock. As a result, agate often is found as a round nodule, with concentric bands like the rings of a tree trunk. The bands sometimes look like eyes, sometimes fanciful scallops, or even a landscape with dendrite trees.
In ancient times Agate was highly valued as a talisman or amulet, it was also said to quench thirst and protect from fevers. And there are legends that tell us that Persian magicians used agate to divert storms.
A famous collection of three thousand agate bowls which was accumulated by Mithradates, King of Pontus, shows the enthusiasm with which agate was regarded in the past. Agate bowls were also popular during the Byzantine Empire. Collecting agate bowls became common among European royalty during the Renaissance and many museums in Europe, including the Louver, have spectacular examples.