Agate heart (Penguin Agate) 100% natural, 30-40mm from Madagascar

Agate is a transparent, but sometimes opaque variety of quartz and a sub-variety of chalcedony. The chemical structure of agate is identical to jasper, flint, chert and is often found together with opal. The colorful, striped specimens are used as semi-precious stones. The name agate comes from the Greek Ἀχάτης, Achatès, the name of the current river Dirillo in southern Sicily, where agates and other chalcedony were found. Traditionally, agate was worn as a lucky stone or for healing. Agate was also made into consumer items such as buttons. A number of medicinal properties are attributed to agate, such as protection during pregnancy, against headaches, skin conditions and balance disorders. According to various literature, agate belongs to the zodiac signs Aquarius, Taurus, Scorpio and Gemini. Agate compounds form as a solution of silicic acid in cavities in older rocks. The stones can be artificially stained to obtain color combinations that are more vivid than those found in nature. The main sources of agate are Brazil, Uruguay and the United States (Oregon, Washington and around Lake Superior). Closer to the Netherlands and Belgium, agate is also found in the Hunsrück in Germany.