Palenzonaite

Palenzonaite
General
CategoryVanadate minerals, garnet supergroup, berzeliite group
Formula(NaCa2)Mn2+2(VO4)3
IMA symbolPlz
Strunz classification8.AC.25
Crystal systemIsometric
Crystal classm3m (4/m 3 2/m) - Hexoctahedral
Space groupIa3d (space group 230)
Unit cell1,969.11 Å3
Identification
ColourDark red
CleavageNone observed
FractureIrregular/uneven, sub-conchoidal
TenacityBrittle
Mohs scale hardness5 - 5½
LusterAdamantine, sub-adamantine, greasy
StreakBrownish red
Specific gravity3.63
Density3.63 g/cm3 (Measured) 3.78 g/cm3 (Calculated)
Refractive indexn = 1.965
BirefringenceIsotropic minerals have no birefringence
PleochroismNon-pleochroic
Ultraviolet fluorescenceNot fluorescent
SolubilitySoluble in strong acids
Alters to32 : Ba/Mn/Pb/Zn deposits, including metamorphic deposits
References[1]

Palenzonaite is a rare vanadate mineral which is a member of the berzeliite group and is related to garnet. It was discovered in 1987 by Andrea Palenzona, Professor of Chemistry at the University of Genoa. He discovered palenzonaite at Molinello mine in Val Graveglia, Liguria Italy.[2]

Palenzonaite is part of a small mineral family (with schaferite, berzeliite, manganberzeliite). The (As,V,P,Si)O4 tetrahedra in these garnets are isolated, not polymerized chains or sheets. Their mean Z–O distance follows the expected trend with ionic radius (shorter for Si4+, longer for As5+/V5+). Palenzonaite shows up as a rare secondary mineral in Mn-rich, low-grade metamorphic deposits.[3]

See also

References

  1. ^ "Palenzonaite". www.mindat.org. 3 December 2025. Retrieved 3 December 2025.
  2. ^ Scott, Michael (3 December 2025). "RRUFF – Comprehensive Database of Mineral Data – Join the RRUFF.net RAMAN Community". Rruf. Retrieved 3 December 2025.
  3. ^ Nagashima, M.; Armbruster, T. (October 2012). "Palenzonaite, berzeliite, and manganberzeliite: (As 5+ , V 5+ , Si 4+ )O 4 tetrahedra in garnet structures". Mineralogical Magazine. 76 (5): 1081–1097. Bibcode:2012MinM...76.1081N. doi:10.1180/minmag.2012.076.5.02. Retrieved 3 December 2025.