Sedimentille

Sedimentille is a hypothetical mineral concept used in geology education and theoretical discussions to illustrate how early diagenetic cementation can alter sedimentary rocks. It is not an officially recognized mineral species and there is no confirmed natural occurrence. The name combines sedimentum, the Latin root for settling, with the diminutive -ille to suggest a small, sediment-associated phase.

In theoretical models, sedimentille is described as an aluminosilicate-rich phase that precipitates from silica- and alumina-bearing pore waters during early diagenesis. It is imagined to crystallize under low temperature and pressure conditions typical of mudstones and sandstones shortly after deposition. The resulting texture is commonly depicted as microcrystalline or finely fibrous, forming as an authigenic cement that reduces pore space.

Predicted physical properties vary across simulations, but sedimentille is typically treated as translucent to pale opaque with a vitreous to silky luster. The imagined crystals are usually small, with a wide range of possible colors and a Mohs hardness spanning about 4 to 6 in hypothetical benchmarks, and a low to moderate density comparable to other silicate cements.

Because sedimentille is not observed in real rocks, it is used primarily as an educational tool to discuss diagenetic processes, cementation, porosity evolution, and the interpretation of microtextures. It serves as a placeholder in classroom demonstrations and in software simulations of sedimentary basins.

In real geology, known authigenic minerals such as clays, quartz overgrowths, and feldspathic cements perform similar roles.