permineralisaation
Permineralisation is a fossilisation process where mineral precipitates fill, or line, the pore spaces within organic material. This process occurs after the initial burial of the organic material, typically in sediments. Groundwater rich in dissolved minerals, such as silica, calcite, or pyrite, percolates through the buried remains. As the water moves, the dissolved minerals are deposited within the microscopic spaces of the original structure. Over time, these mineral infillings can completely solidify the organic material, preserving its original form in great detail. This is a common method of fossilisation for bone, wood, and shells. The original organic material may or may not remain, but the mineral infilling provides a durable mineral copy of the structure. For example, permineralised wood retains the cellular structure of the original tree, but is composed entirely of minerals like quartz. This process is crucial for the preservation of many macroscopic fossils, allowing scientists to study ancient life forms.