Petrified opal, often referred to as opalized wood, is a type of fossilized wood that, over millions of years, has had its organic material replaced by opal, a hydrated form of silica. This process, known as permineralization, occurs when the wood becomes buried under sediment and is infused with mineral-laden water. As the water evaporates or recedes, the minerals are left behind, replacing the wooden structure cell by cell with silica and creating a stone-like replica of the original wood.
What makes petrified opal incredibly fascinating is that it captures, in stunning detail, the original structure of the ancient wood, down to its growth rings and grain. This results in a fossil that not only reveals the history of the tree but also displays the unique iridescence of opal, often with beautiful patterns and a spectrum of colors, of which blue is a particularly sought-after hue.
