Aquamarine with schorl tourmaline, Erongo Region, Namibia
Scheelite on muscovite; Sichuan Province of China
Corundum var. Ruby Sabaragamuwa Province, Sri Lanka
Apophyllite with Scolecite; Maharashtra, India
Metatorbernite; Midi-Pyrenees, France
Rhodochrosite; Santa Eulalia, Chihuahua, Mexico
Aquamarine with fluorite and muscovite; Gilgit District, Pakistan
These are all cross sections of stalactites, which occur when minerals form in long, tube-like shapes. They typically form in caves or hollow spots in rocks where they have plenty of room and time to grow. Featuring amethyst (SiO2),malachite (Cu2CO3(OH)2), azurite (Cu3(CO3)2(OH)2) and malachite, and rhodochrosite (MnCO3).
Native gold with quartz; Eagle’s Nest Mine, Placer County, California
Amethyst and smoky quartz; Brandberg Area, Erongo Region, Namibia
