Paramelaconite

Paramelaconite
Paramelaconite from the Copper Queen Mine, Cochise County, Arizona, USA
General
CategoryOxide mineral
Formula
(repeating unit)
CuI
2
CuII
2
O3[1] (or Cu4O3)[2]
IMA symbolPml[3]
Strunz classification4.AA.15
Dana classification4.6.4.1
Crystal systemTetragonal
Crystal classDitetragonal dipyramidal (4/mmm)
H-M group: (4/m 2/m 2/m)
Space groupI41/amd {I41/a 2/m 2/d}
Unit cella = 5.837 Å,
c = 9.932 Å; Z = 4[1]
Identification
ColorBlack to black with a slight purple tint
White with pinkish brown tint in reflected light
Crystal habitOccurs as striated prismatic crystals; massive
CleavageNone observed
FractureConchoidal
TenacityBrittle
Mohs scale hardness4.5
LusterSub-adamantine, greasy, sub-metallic
StreakBrown-black
DiaphaneityOpaque
Specific gravity6.04–6.11 (measured)
Optical propertiesUniaxial[1]
PleochroismWeak
Ultraviolet fluorescenceNot fluorescent
SolubilitySoluble in HCl and HNO3[4]
References[5]

Paramelaconite is a rare, black-colored copper(I,II) oxide mineral with formula CuI
2
CuII
2
O3 (or Cu4O3). It was discovered in the Copper Queen Mine in Bisbee, Arizona, about 1890. It was described in 1892 and more fully in 1941. Its name is derived from the Greek word for "near" and the similar mineral melaconite, now known as tenorite.

  1. ^ a b c Cite error: The named reference handbook was invoked but never defined (see the help page).
  2. ^ Morgan et al. 1996, p. 33.
  3. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. doi:10.1180/mgm.2021.43. S2CID 235729616.
  4. ^ Koenig 1892, p. 287.
  5. ^ Cite error: The named reference mindat was invoked but never defined (see the help page).