Petrified wood is a type of fossil: it consists of wood where all the organic materials have been replaced with minerals (most often a silicate, such as quartz), while retaining the original structure of the wood. The petrifaction process occurs underground, when wood becomes buried under sediment. Mineral-rich water flowing through the sediment deposits minerals in the plant's cells and as the plant's lignin and cellulose decay away, a stone mould forms in its place.
Elements such as manganese, iron and copper in the water/mud during the petrification process give petrified wood a variety of color ranges. Pure quartz crystals are colorless, but when contaminants are added to the process the crystals take on a yellow, red or other tint.
Petrified wood can preserve the original structure of the wood in all its detail, down to the microsopic level. Structures such as tree rings and the various tissues are often observed features.
Petrified wood: The name comes from the Greek "petro" or "rock", and refers to wood that has been turned to stone. The process of petrification preserves parts of ancient trees in fossil form. When the wood becomes buried under sediment, mineral-rich water flows through the sediment and replaces the cells' structure with minerals, producing a very good stone copy of the original piece of wood. The predominant minerals in petrified wood are silicates, such as quartz.
It's quite wondrous to examine a piece of petrified wood, knowing that it represents part of a hugh forest existing millions of year ago.
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