Hard Wood, Petrified Forest-AZ
Petrified Forest National Park, Arizona
Over 200 million years ago, the logs washed into an ancient river system and were buried quick enough and deep enough by massive amounts of sediment and debris also carried in the water, that oxygen was cut off and decay slowed to a process that would now take centuries.
Petrified wood is almost solid quartz, weighing in at 168 pounds per cubic foot. It's so hard, you can only cut it with a diamond tipped saw!
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Uploaded on September 16, 2009