A weathered wooden sign, presented by Disney, details the "Petrified Tree" from the Pike Petrified Forest, Colorado, weighing five tons and measuring 7/2 feet in diameter. It was part of a sub-tropical forest that was estimated to have been 200 feet tall, and was part of a larger forest that was 55 to 70 million years old. Scientists believe it to be of the redwood of Sequoia, and during some historic eras, silica was heated to overspread the living-forest, wood cells were changed, opals were formed within the tree trunk itself.