look on all sides. try to find either long lines, like a piece of plywood would have. this isusually grain wood. also look for dots (cell structures) on the top or bottom of the rock. these are palm wood, easily distinguished by the dots (cell structures) in the wood.
petrified palm wood
The Petrified Forest of Argentina is located in Sarmiento, Argentina. Its petrified wood stems from palm trees and conifers, and dates back to the Cenozoic Era.
Petrified Wood
Paper, wood, quartz
Texas does not have a State Mineral, but the State Rock is petrified palm wood, and the State Gemstone is blue topaz.
The streak of petrified wood is black or brown. The streak can also be white.
...the petrified forest...
petrified wood
Petrified wood.
Petrified wood rates between 7 and 8 on Moh's Hardness Scale
The Petrirfied Forest is a forestis petrified that petrified by wood in the Petrified Forest. Wirten By Valeria Roman Barrios 23
Petrified wood has turned to stone, a type of fossil, It is unlikley that you would be able to burn it.