Multimeetrite

Multimeetrite is a fictional mineral species frequently used in mineralogy and crystallography teaching to illustrate how multiple stacking and meet-point arrangements can produce polytypic structures in layered silicates. It is not observed in nature and is treated as a theoretical example rather than a real mineral.

In the hypothetical model, multimeetrite is described as a layered silicate with alternating sheets that allow various cationic interlayers. The concept emphasizes how different stacking sequences and interlayer contacts can generate distinct polytypes from a single chemical system. Because it is a construct for pedagogy, its proposed composition and structure are intentionally flexible, focusing on the principles of crystallography rather than a fixed, experimentally verified formula.

Physical properties attributed to multimeetrite in teaching contexts typically include a vitreous to pearly luster, a hardness around 5.5–6 on the Mohs scale, and a density in the low to mid 3 g/cm3 range. Color is often described as pale green to brown in hypothetical samples, with cleavage that reflects its layered nature and a conchoidal to uneven fracture pattern in other directions. These attributes are illustrative rather than empirically observed, intended to demonstrate how layering and polytypism influence observable traits.

Occurrence and synthesis are described as laboratory demonstrations rather than natural discoveries. In demonstrations, multimeetrite-like specimens can be synthesized under controlled high-temperature, high-pressure conditions to explore phase transitions and stacking variants. Etymology reflects its “multi” and “meet” origins, with the common mineral suffix -rite used to indicate a crystalline solid.