Petrification is the process of turning plant material into stone. This is done by infiltration with water that carries mineral particles. The original shape of the item remains unchanged after the process.
The petrification of wood is a common example of this process. In 1906, George Weber Wieland presented a theory proposing that wood petrification is based on five factors. Those factors include the tissue systems of the plant, temperature, minerals needed for silification or calcification, the duration of the chemical activity, and the nature of the embedding rock material.
The time it takes for petrification to occur varies depending on the minerals used. In general, the process takes a few hundred years to complete.