Wood Opalite is a type of petrified wood that has been impregnated with the Silicon Dioxide commonly known as Opal. Wood Opalite occurs in a range of colors, primarily earth tones, including browns, grays, and creams. Petrified wood is created through a process called permineralization, which takes millions of years. When wood becomes covered with earth, decays and is exposed to mineral-rich water, mineral deposits can create stone in the place of the decaying wood. Through this process, all organic parts are replaced by minerals, while retaining the structure of the wood. Wood Opalite, also know as Fossilized Wood, Agatized Wood As with all natural stones, colour and look may differ from strand to strand and even from bead to bead. Beads: Round 4mm - 20cm strand Round 6mm - 20cm strand Round 10mm - 20cm strand Rondelle 6mm - 20cm strand Coin (Puffed) 8mm - 20cm stand Large Beads: Coin (Flat) 30mm - 1 piece Free Form 26mmx 40mm - 1 piece