Featured in this lot is this 43lb, 14oz. Montana collected petrified wood mineral deposit collected 20th century. The petrified wood slab shows crystal formations and mineral deposits. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment or volcanic ash and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition. Mineral-laden water flowing through the covering material deposits minerals in the plant's cells; as the plant's decay, a stone mold forms in its place. The organic matter needs to become petrified before it decomposes completely. The process lasts millions of years. All the organic materials have been replaced with minerals while retaining the original structure of the limb. The condition of this sample of petrified wood is well preserved with no alterations and an all natural look which displays an overall well preserved condition. The measurement is 8.75"W x 16.5"L x 4.25"D, weight is 31lb, 12oz