New tumbled stones in 2025, petrified wood from Turkey.

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referred to as petrified wood, is a type of fossil: it consists of fossil wood, in which all organic materials have been replaced by minerals (usually silicates, such as quartz) while retaining the structure of the wood. Subterranean burial of a tree under sediment initiates the petrification process, which can span millions of years. Groundwater that slowly seeps through the soil deposits minerals where the lignin and cellulose rot away. If the deposition and rotting are equally fast, the shape of the cells is preserved. The smallest details can be immortalised. Petrified annual rings and various tissues can be traced down to a microscopic level. Petrified wood has a hardness of 7 on the Mohs scale of hardness, the same as quartz. We have now reduced the petrification process to a few days in a laboratory. Petrified wood occurs in a wide range of colours due to variations in the deposits of minerals such as manganese, iron, and copper. Quartz is colourless, but when iron is added, it forms crystals with a red or yellow tinge, 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 The colour of silica is either white or grey. Localities: Argentina The Petrified Forest National Monument in Santa Cruz, Argentina, is considered one of the world's best-preserved petrified forests; many of the petrified trees in Patagonia are over 3 metres in diameter and over 30 metres tall. Belgium: the Goudberg geosite near Hoegaarden. *Greece: The Petrified Forest at Sigri on the western tip of the island of Lesbos is probably the largest petrified forest, over 150 km². There are trunks that are up to 22 meters long. Large trees, complete with their roots, still stand upright. It has been a protected natural monument since 1985. *Kerguelen: Researchers have discovered ninety million-year-old petrified forest remains on the French islands. *Namibia: Rivers from the north likely transported the petrified tree trunks near Khorixas to Namibia. Some recognisable trunks are 30 m long. *Austria: Near Laas, in the state of Carinthia, one can find the remains of a petrified forest. * 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 have a diameter of about 1.8 m and are therefore significantly smaller than those in South America. A famous park is the Petrified Forest National Park in the state of Arizona.