Petrified Wood Millions of Years Old

Whilst most prehistoric trees that fell decomposed, some were preserved after being buried by sediment or volcanic ash.  This starved them of oxygen which prevented decay from immediately setting in. 

Minerals being in carried in groundwater slowly seeped into the organic matter.  Over time as the water dried up the minerals crystallised.  With the water being rich in iron, when it combined with quartz during the process of petrifaction many colours were produced.

'Petrifaction' is a geological process that enables the organic matter to be transformed into stone.  The word comes from Greek for 'wood turned into stone'. 

It takes millions of years for wood to become petrified.  Although some believe it's the organic matter that turned to stone, this is not the case.  As the wood decayed it was replaced with natural minerals which created an internal cast.  The original cell walls of the tree often remained intact.

This subtle coloured petrified wood slice is highly polished on one side only.