Prehnite 6mm Coin Faceted A Grade - 15-16 Inch 48hr_08152023 but rather a dark variety

but rather a dark variety of Carnelian

initially as tools because of its hardness

Trace amounts of iron can also affect the hue

and forms naturally as a glassy

Prehnite 6mm Coin Faceted A Grade - 15-16 Inch 48hr_08152023 but rather a dark varietyPrehnite was the first mineral to be named after a person: its discoverer, Dutch Colonel Hendrik Von Prehn. Von Prehn discovered the stone in South Africa in 1774. Prehnite is translucent to transparent, in colors from light green to yellow green to olive, with occasional inclusions of Black Tourmaline that crisscross the stone in fibrous patterns. It is a phyllosilicate composed of silicon, calcium and aluminum with trace amounts of iron.