felsparia
Felsparia is a mineral described as a rare member of the feldspar group, an aluminosilicate with a framework of alternating silicon and aluminium tetrahedra. It commonly forms prismatic crystals that are colorless to pale green, with a vitreous luster. Typical physical properties include a Mohs hardness around 6.5 and a density near 2.58–2.70 g/cm3. In hand specimen it is usually accompanied by quartz and other pegmatite minerals, and under polarized light it exhibits low birefringence.
Composition and structure are dominated by a substitutional chemistry written as (K,Na)AlSi3O8, with minor substitutions of
Geological occurrence and formation conditions suggest felsparia crystallizes in late-stage granitic pegmatites, forming from highly evolved
Discovery and naming: felsparia was described in a mid- to late-20th-century mineralogical report, with the name
Uses and significance: due to its distinct lattice parameters and potential minor luminescent properties, felsparia is