Petrified wood is basically fossilized wood that has had it’s organic matter replaced by stone, bit by bit, as it decomposes. The wood structure is maintained, but the wood fibers are slowly changed into stone. Sometimes a jasper, quartz, pyrite or even opal can be found fossilized in wood. More often than not its coloring is brown, but it has been found in grey and even green color.
Petrified wood comes from Argentina, Egypt and the Czech Republic, but the most famous source is of course The Petrified National Forest Park in Arizona. This material is quite heavy and has a Mohs hardness similar to the agate.
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