#mineralogy terms

• Aplotite — A rare variety of gneissic vein rock or fine granitic gneiss, characterized by a well-defined aplitic or microgranular structure. This geological body is structurally composed mainly of quartz, plagioclase feldspar, and white micas, exhibiting a flattened or schistose macroscopic appearance due to metamorphic tectonic pressures exerted along the crystalline axes.
• Areniform — Having the shape, appearance, or texture of sand; granular, gritty, or pulverulent, visually or structurally resembling a mass of fine quartz grains. In a mineralogical and industrial sense, the term describes substances, crystalline aggregates, or technical powders presenting as tiny, loose, and unpolished particles that do not strongly adhere to one another.
• Argilliform — Having the shape, appearance, or physical properties of clay; mineral masses or fine sedimentary deposits featuring a plastic, compact, and colloidal structure resembling clay. In a geological sense, it describes materials resulting from the profound weathering of silicates, capable of becoming malleable in the presence of water and maintaining their shape upon drying according to standard textural parameters.
• Argilloid — Having the appearance, texture, or colloidal properties of clay without being a pure clay from a mineralogical standpoint; a synthetic or natural material or aggregate that mimics the plastic structure of clay. In a geological sense, it describes partially weathered minerals or silicates that have developed a fine consistency and a temporary capacity for reversible hydration resembling clay.