Prehnite 10mm Round AAA Grade - 15-16 Inch Barrel Blue deep-blue copper mineral produced by

deep-blue copper mineral produced by weathering of copper ore deposits

usually in white on hues of brown

The blue colors are photosensitive and may fade when exposed to excessive light or heat

This item is treated and dyed agate

Tiger Eye is a macrocrystalline Quartz stone with bands of rich golds and browns

Prehnite 10mm Round AAA Grade - 15-16 Inch Barrel Blue deep-blue copper mineral produced byPrehnite 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.