Aquamarine on Black Tourmaline - Erongo Mountains, Namibia

A lone, pale blue aquamarine crystal sits atop a lusterous, well-terminated chunk of schorl from the Erongo Mountains in Namibia. Although the schorl has broken away from the host rock, the crystal is in overall good shape, and displays nicely on a flat surface.

Beryl is a mineral that's composed of beryllium aluminum cyclosilicate, with the chemical formula Be3Al2(SiO3)6. Naturally occurring beryl tends to form hexagonal crystals that can reach several meters in size if given the right conditions. Completely pure beryl will be transparent and colorless, while mineral impurities frequently tint the crystals color in most specimens.

Well known varieties of beryl include aquamarine and emerald, although beryl can also be green, blue, yellow, white and red, depending on the incorporated impurities during formation. Red beryl is known to be the most rare form of beryl found and is currently only known to be found in New Mexico and Utah.
Tourmaline is a crystalline boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Schorl, or black tourmaline, is the most common form of tourmaline, and has been used for everything from jewelry to piezoelectric guitar pickups.
Aquamarine, Tourmaline
Erongo Mountains, Namibia
Aquamarine is .39x.25" on 2x1.59x1.29" Schorl