Spongolite

thumb|240px|Spongolite texture, click to enlarge (2MB)

Spongolite (also spelled spongilite, spongillite, or spongiolite) is a sediment or sedimentary rock composed principally of the remains of largely articulated fossils of rigid-bodied siliceous sponges. In contrast, spiculite is either sediment or sedimentary rock composed of mostly disarticulated, discrete siliceous sponge spicules. As seen below, in some older papers, spongolite is used as a synonym of spiculite.