Petrified wood from Banten, Indonesia (0.5-10kilo)

Petrified wood, also referred to as petrified wood, is a type of fossil: it consists of fossil wood, in which all organic materials have been replaced by minerals (usually silicates, such as quartz), while preserving the structure of the wood. The process of petrification happens underground, when a tree becomes engulfed in sediment, and can take millions of years. Groundwater that slowly seeps through the soil deposits minerals where the lignin and cellulose rot. If the deposition and rotting proceed at the same rate, the shape of the cells is maintained. The smallest details can be immortalized. Petrified growth rings and various tissues can be traced down to a microscopic level. Petrified wood has a hardness of 7 on the Mohs hardness scale, the same as quartz. The petrification process has now been reduced to a few days in a laboratory. Petrified wood occurs in a wide spectrum of colors due to variation in the deposits of minerals such as manganese, iron and copper. Quartz is colorless, but when iron is added it produces crystals with a red or yellow hue, as shown in the list below: Carbon – Black Cobalt – Green/Blue Chromium – Green/Blue Copper – Green/Blue Iron Oxides – Red, Brown, yellow Manganese - pink/orange Manganese oxides - black Silica - white, gray. Sites: Argentina: The Petrified Forest National Monument in Santa Cruz, Argentina, is considered one of the world's best-preserved petrified forests; many petrified trees in Patagonia are more than 3 meters in diameter and longer than 30 meters. Belgium: the Goudberg geosite near Hoegaarden *Greece: The Petrified Forest near Sigri on the western tip of the island of Lesbos is probably the largest petrified forest, more than 150 km². There are trunks up to 22 meters long. Large trees, complete with their roots, still stand upright. It has been a protected natural monument since 1985. *Kerguelen: on the French islands remains of fossilized forests that are 90 million years old have been found. *Namibia: The petrified trees near Khorixas were probably transported as logs over rivers, from the north, to Namibia. Some recognizable trunks are 30 m long. *Austria: in the state of Carinthia, there are remains of a petrified forest near Laas. *Czech Republic: The largest stone is located in the Nová Paka museum village and is 8.20 m long. *United States: The largest specimens in the country are approximately 1.8 m in diameter, so they are significantly smaller than those in southern America. A famous park is the Petrified Forest National Park in the state of Arizona.