Madagascar Dendiritc Green Opal 10mm Round A Grade - 15-16 Inch 6-8x12-25mm Blue Tiger Eye is a

Blue Tiger Eye is a naturally occurring dark stone with chatoyant layers that create a flash which seems to emanate from within the stone as they catch the light

Biotite is a name used for a large group of black mica minerals that are commonly found in igneous and metamorphic rocks

however they are not currently sourced from that particular region

or some degree of pink in between

Madagascar Dendiritc Green Opal 10mm Round A Grade - 15-16 Inch 6-8x12-25mm Blue Tiger Eye is aThis variety of opal is named "dendritic" for the small inclusions within it that resemble moss or ferns. These inclusions consist of iron, manganese and other metallic oxides captured during the forming of the rock. Opals are hydrated amorphous forms of silica, created when silica hardens within the fissures of other stones.