CHALCEDONY GemShoppy April 28, 2015 Gemstones Chalcedony promotes calm and peace. Stone’s names: Chalcedony, Calcedony. Chalcedony can be virtually any colour of the rainbow. It is commonly pale blue, yellow, brown or grey with nearly wax like lustre. A white, buff, or light tan species of chalcedony are also occurred. SiO2 Chalcedony is a finely crystallized or fibrous quartz that forms rounded crusts, rinds, or stalactites in volcanic & sedimentary rocks. Chalcedony is a precious stone that occurs in many forms, colours, and shapes. Chalcedony, agates, jaspers, bloodstone, cornelian, onyx, and chrysoprase all make up the chalcedony gemstones. Chalcedonic pseudomorphs after other minerals often give rise to very interesting specimens. Other physical properties are those of quartz. Protect chalcedony from scratches, sharp blows, harsh chemicals and extreme temperatures. From the stone history: The Romans prized chalcedony as seals, and the Victorians carved them into an endless array of cameos and intaglios. Chalcedony was used in Renaissance magic for health & safety. In all ages chalcedony has been the stone most used by the gem engraver, many colored varieties are still cut polished as ornamental stones.