New Lander + 14kt Gold-filled posts + pure copper bezel cups: These are natural untreated Chalcosiderite stones from the NEVADA New Lander Mine. The New Lander Mine produces Turquoise, Chalcosiderite and Faustite. All are listed within the Turquoise family of minerals. If a vein is Aluminum rich, then it is considered Turquoise, if it is Iron rich, then it is considered Chalcosiderite and lastly, if Zinc rich, then it is considered Faustite. All are valuable, collectible and beautiful.