Terry O’Connor delves into the fascinating transformation of deceased bodies into blue-hued remains due to the formation of the mineral vivianite. This process occurs in specific conditions, where iron from the environment reacts with phosphate from decaying bodies, resulting in stunning blue crystals scattered over bones, teeth, skin, and even adipocere. Vivianite can complicate forensic investigations by hindering DNA analysis, as seen in various cases throughout history. However, vivianite also serves to protect human remains, slowing decay and offering insights into burial practices and environmental conditions. This mineral, along with other substances like blue-green copper minerals, adds an unexpected and colorful twist to the process of decomposition.
https://www.atlasobscura.com/articles/vivianite-blue-human-remains