Dendritic opal heart B merkabite much of which is formed

much of which is formed from the shells of dead marine organisms

Agave americana is known as century plant but it typically only lives between 10 and 30 years

Deposits have been found in Afghanistan

Gem quality transparent sphalerite is rare

his opaque

Dendritic opal heart B merkabite much of which is formedDendritic Opals are unique in the Opal family they form when water rich percolating mineral solutions containing manganese & iron flows along naturally occurring fractures, fissures & bedding planes. This type of opal features dendrites, which are fern like inclusions of iron, manganese, or other metallic oxides that create bold patterns within the gem. Typically, dendritic opals are cut into slices to best exhibit nature's artwork.