Je vous emmène à travers mes vidéos découvrir mon expérience acquise depuis plus de 30 ans a silloner le globe entier à la recherche de pierres précieuses, de rencontre mémorables mais aussi de difficulté parfois …
Chalcedony: This is a term including microcristallines and cryptocrystalline varieties of quartz, which come from the Greek name of the famous city of Carthage “Karkêdon”. Extracted in Egypt and Syria, it has been used since ancient times for intaglios and cameos, an active trade with
It is its discovery near the town of Conseilheira Pena, in Minas Gerais (Brazil) in 1945 by Pough, which gave its name (Brazil is written Brasil in Brazilian).
It takes its name from the mine Bastnas Riddarhyttan in Vastmanland in Sweden where it was discovered. There are three varieties of bastnaesite based on the predominant “rare earth element” (rare metallic chemical elements) in it. Here lanthanum is the dominating but also cerium can
Discovered in 1824 in England, it was named after its composition, it contains barium as much as barite and it is a carbonate (calcium, as calcite, but with the addition of barium).
