Madagascar Dendiritc Green Opal 8mm Round A Grade - 15-16 Inch Green Aventurine (AAA) and sometimes lepidolite

and sometimes lepidolite

It sometimes features dark brown to black dendritic inclusions that branch like tiny tree limbs through the stone

but a combination of minerals

found in Thailand/Indonesia

soft and glassy stone

Madagascar Dendiritc Green Opal 8mm Round A Grade - 15-16 Inch Green Aventurine (AAA) and sometimes lepidoliteThis 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.