Wikipedia
Permineralization
Permineralization is a process of fossilization in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of plants.
Usage examples of "permineralization".
More often, moisture filtering down through the sediment will pick up minerals and then deposit them again in the interstices of the bone, or replace the bone altogether, a process called permineralization, which effectively turns bone to rock.