LARGE Petrified Wood Bookends - Arizona b591f35a162063903eaa896b6828cf2c Aragonite and Calcite are similar

Aragonite and Calcite are similar in chemical composition (polymorphs) but are structured differently

Sulfur is essential to all living organisms as minor amounts exist in body fluids

but there must have been at least several

Moldavite is a unique type of Tektite

it may very well have been that Neanderthal and Modern Man could have seen each other's camp fires between the Straight of Gibraltar

LARGE Petrified Wood Bookends - Arizona b591f35a162063903eaa896b6828cf2c Aragonite and Calcite are similarFrom ancient Greek meaning "wood turned into rock", Petrified Wood is a form of fossilization where all the organic matter combines with minerals (usually a silicate, such as quartz) during a process called per mineralization. In order for wood to become petrified it must be completely covered by sediment, thereby depriving the wood of oxygen. Simultaneously, there must be a mineral rich water source close by. Over time, the water delivers the