The amphibole group is very large and extremely complex and contains numerous distinct species that vary subtly in chemistry and physical properties. Pargasite and ferropargasite are calcic amphiboles that generally are lumped together as hornblende,even though up to 16 distinct minerals belong to this group, including actinolite. The identity of a specific amphibole is determined (ideally) by a chemical analysis or by detailed measurements of density, color, and optical data. There are undoubtedly a great many localities that could potentially yield cuttable crystals.
See also: Actinolite; Hornblende; Amphibole; Series to Ferropargasite if Fe exceeds Mg.
Amphibole Group; closely related to Hornblende.
Optics: a=1.613; β= 1.618; γ=1.635.
Biaxial (+), 2V: 120°.
Occurrence: A widespread component of igneous and metamorphic rocks.
Pargas, Finland.
Scotland; Sweden; Russia; Austria; Venezuela.
Canada: Baffin Island, Nunavut; Nova Scotia.
United States: Fresno, California; Burlington, Pennsylvania.
Comments: The amphibole group is very large and extremely complex and contains numerous distinct species that vary subtly in chemistry and physical properties. Pargasite and ferropargasite are calcic amphiboles that generally are lumped together as hornblende, even though up to 16 distinct minerals belong to this group, including actinolite. The identity of a specific amphibole is determined (ideally) by a chemical analysis or by detailed measurements of density, color, and optical data. There are undoubtedly a great many localities that could potentially yield cuttable crystals.
Name: After the locality, Pargas, Finland.