BOISF-B-01 Origin: Brazil Grade: A Dimensions: Approximately 25-40mm Weight: Between 25-35g Origin: Madagascar Grade: A = good Raw fossilized or petrified wood stone approximately 25-40mm Sold individually. Colors and patterns vary from one stone to another. Fossil wood is one of nature's many peculiarities. This fossil wood is both half stone / half wood. It is also called petrified wood, silicified wood, or xyloid. Indeed, the tree has transformed into stone through the process of petrification. The term petrified wood comes from the Greek petro, meaning "stone." Fossil wood is the result of a very long transformation that began millions of years ago, during the prehistoric era.