Dendritic Black Opal 4mm Round - 15-16 Inch hps_05162024 Delicate veining

Delicate veining

It is sometimes used for scalpel blades in cardiac surgery

grinding wheels and cutting disks

Stromatolites date back more than three billion years and are the oldest known fossils

creating fascinating patterns

Dendritic Black Opal 4mm Round - 15-16 Inch hps_05162024 Delicate veiningThis 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.