Prehnite 13x16mm Center Drilled Faceted Pear Bead - 15-16 Inch R0911 The best available information indicates

The best available information indicates that the stone is a type of Dolomite that has been altered by volcanic activity

and beads per strand counts may vary slightly from what is shown

a turquoise trader and an electrical engineer

Common opals are classed as a mineraloid

Sonoran Gold is not mined in veins but rather as individual nuggets typically found in clay deposits

Prehnite 13x16mm Center Drilled Faceted Pear Bead - 15-16 Inch R0911 The best available information indicatesPrehnite 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.