crystalloïde

Crystalloïde is a term used in geology and mineralogy to describe substances that are not crystalline. This means that their constituent atoms or molecules are not arranged in a regular, repeating three-dimensional lattice structure. Instead, their particles are disordered, lacking the long-range order characteristic of crystals.

Glass is a common example of a crystalloïde material. In glass, silicon dioxide molecules are bonded in a random, network-like fashion, lacking the ordered arrangement found in quartz, which is a crystalline form of silicon dioxide. Other examples of crystalloïde materials include amorphous solids and some types of plastics.

The distinction between crystalline and crystalloïde materials is fundamental in understanding their physical and optical properties. Crystalline materials often exhibit anisotropic behavior, meaning their properties vary depending on the direction within the crystal. Crystalloïde materials, on the other hand, are typically isotropic, with properties being the same in all directions. This difference arises directly from their internal structural order or lack thereof. The term crystalloïde is sometimes used interchangeably with amorphous, though specific contexts may draw subtle distinctions.