Chanabayaite

Chanabayaite
General
Category	Organic mineral
Formula	Cu 2(N 3C 2H 2Cl(NH 3,Cl,H 2O,[]) 4
IMA symbol	Cba [1]
Crystal system	Orthorhombic
Crystal class	Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m)
Space group	Imma
Unit cell	a = 19.48, b = 7.21, c = 11.999 [Å] (approximated); Z = 4
Identification
Color	Blue
Crystal habit	Prisms (imperfect); radial aggregates
Cleavage	(001), perfect; (100) and (010), imperfect
Tenacity	Brittle
Mohs scale hardness	2
Density	1.48 (measured)
Pleochroism	Deep blue to pale blue with gray hue (strong)
References	[2] [3] [4]

Chanabayaite is the first recognized triazolate mineral, having the formula Cu
_²(N
_³C
_²H
_²Cl(NH
_³,Cl,H
_²O,[])
_⁴.

Minor iron admixture is also present. ^[3] It is also one of a few currently known minerals containing ammine groups, including also ammineite, joanneumite and shilovite. ^{[5] [6] [7]} All the minerals are rare and were found in a single guano deposit in Chile, called Pabellón de Pica. ^[4] A similar natural phase, formula NaCu
_²Cl
_³[N
_³C
_²H
_²]
_²[NH
_³]
_²•4H
_²O, likely a precursor of chanabayaite, is described by Zubkova et al. 2016. ^[8]

Crystal structure

The main features of the crystal structure of chanabayaite are: ^[3]

• copper forms octahedra, part of which share corners
• 1,2,4-triazolate anions link the octahedra

Association

Chanabayaite coexists with halite, joanneumite, nitratine, salammoniac and paragenetically-unrelated chalcopyrite. Chalcopyrite is present in an amphibole- and plagioclase-bearing gabbro, that contacts the guano deposit. ^[3]

Formation

Three suggested processes account for the formation of chanabayaite: ^[3]

• leaching of sodium from the precursor phase
• leaching of chlorine from the precursor phase
• partial dehydratation of the precursor phase

References

1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
2. Mineralienatlas
3. Chukanov, N.V., Zubkova, N.V., Möhn, G., Pekov, I.V., Pushcharovsky, D.Yu., and Zadov, A.E., 2015. Chanabayaite, Cu2(N₃C₂H₂Cl(NH₃,Cl,H₂O,[])₄, a new mineral containing triazolate anion. Geology of Ore Deposits 57(8), 712-720.
4. "Chanabayaite: Chanabayaite mineral information and data". Mindat.org. Retrieved 2016-03-10.
5. "Ammineite: Ammineite mineral information and data". Mindat.org. Retrieved 2016-03-10.
6. "Joanneumite: Joanneumite mineral information and data". Mindat.org. Retrieved 2016-03-10.
7. "Shilovite: Shilovite mineral information and data". Mindat.org. Retrieved 2016-03-10.
8. Zubkova, N.V., Chukanov, N.V., Pekov, I., and Pushcharovsky, D., 2016. The crystal structure of the natural 1,2,4-triazolate compound NaCu
   _²Cl
   _³[N
   _³C
   _²H
   _²]
   _²[NH
   _³]
   _²•4H
   _²O. Zeitschrift für Kristallographie - Crystalline Materials 231(1), 47–53.