brown
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 …
actualités
oligoclase
ck_admin
March 24, 2021
From the family of plagioclase, its name comes from the Greek “oligo”, a little bit, and “klassos” break, because it is a feldspar whose cleavage is more difficult than for others. It is part of the albite-anorthite series. It was identified by Breithaupt in 1826.
obsidian
ck_admin
March 24, 2021
Its name comes, according to Pliny, from Obsidius who brought it from Ethiopia, which would have led the Romans to call it “obsidius lapis”. From the seventeenth century we find the names of hyalopsite, mountain mahogany, Iceland black agate, mirror of the Incas, gallinaceous stone
muscovite
ck_admin
March 24, 2021
Discovered by the famous mineralogist James Dwight Dana in 1850, it owes its name to the “glass of Moscow” (vitrum muscoviticum), as the large plates, heat-resistant were used as windows for stoves and furnaces in this region. The hardness varies from one to two depending
