Huenite, Cu4Mo3O12(OH)2, is a new copper and molybdenum oxy-hydroxide mineral found in the San Samuel Mine, Carrera Pinto, Cachiyuyo de Llampos district, Copiap´o Province, Atacama Region, Chile. This new species forms flattened orthorhombic prisms up to 60-70 lm in size, weakly elongated along [001]. Huenite crystals were found on fractured surfaces of a quartz breccia, forming aggregates 1 mm in diameter in close association with lindgrenite, gypsum, dark grayish-brown tourmaline, and an unknown pale purple phase. The color is very dark reddish-brown, with a strong vitreous to adamantine luster. Its streak is pale reddish-brown to pinkish. The mineral is brittle with an irregular fracture and a Mohs hardness of 3.5-4 with a good cleavage on {010}. Its calculated density is 5.1 g/cm3. The calculated refractive index is 2.18. Huenite is nonfluorescent under 254 nm (short wave) and 366 nm (long wave) ultraviolet light. The empirical formula, calculated on the basis of 3 (MoþSþSi) atoms per formula unit, is (Cu3.519Fe2þ0.403)R3.922(Mo2.907S0.090Si0.003)R3.000O12(OH)2.229, with H2O content calculated for a total of 100 wt.%. Huenite is trigonal, with space group P31/c and unit-cell parameters a ¼ 7.653(5) ? A, c¼9.411(6) ?A, and V¼477.4(5) ? A3 for Z¼2. The eight strongest measured powder X-ray diffraction lines are: [d in ?A, (I/I0),( hkl)]: 2.974 (100) (112), 1.712 (59.8) (132), 3.810 (50.6) (110), 2.702 (41.2) (022), 2.497 (38.1) (120), 1.450 (37.2) (134), 6.786 (24.9) (010), and 5.374 (24.5) (011). The mineral, which has been approved by the CNMNC under number IMA 2015122, is named in honor of Edgar Huen.
HUENITE, Cu4Mo3O12(OH)2, A NEW COPPER-MOLYBDENUM OXY-HYDROXIDE MINERAL FROM THE SAN SAMUEL MINE, CARRERA PINTO, CACHIYUYO DE LLAMPOS DISTRICT, COPIAPO PROVINCE, ATACAMA REGION, CHILE
Vignola P;
2019
Abstract
Huenite, Cu4Mo3O12(OH)2, is a new copper and molybdenum oxy-hydroxide mineral found in the San Samuel Mine, Carrera Pinto, Cachiyuyo de Llampos district, Copiap´o Province, Atacama Region, Chile. This new species forms flattened orthorhombic prisms up to 60-70 lm in size, weakly elongated along [001]. Huenite crystals were found on fractured surfaces of a quartz breccia, forming aggregates 1 mm in diameter in close association with lindgrenite, gypsum, dark grayish-brown tourmaline, and an unknown pale purple phase. The color is very dark reddish-brown, with a strong vitreous to adamantine luster. Its streak is pale reddish-brown to pinkish. The mineral is brittle with an irregular fracture and a Mohs hardness of 3.5-4 with a good cleavage on {010}. Its calculated density is 5.1 g/cm3. The calculated refractive index is 2.18. Huenite is nonfluorescent under 254 nm (short wave) and 366 nm (long wave) ultraviolet light. The empirical formula, calculated on the basis of 3 (MoþSþSi) atoms per formula unit, is (Cu3.519Fe2þ0.403)R3.922(Mo2.907S0.090Si0.003)R3.000O12(OH)2.229, with H2O content calculated for a total of 100 wt.%. Huenite is trigonal, with space group P31/c and unit-cell parameters a ¼ 7.653(5) ? A, c¼9.411(6) ?A, and V¼477.4(5) ? A3 for Z¼2. The eight strongest measured powder X-ray diffraction lines are: [d in ?A, (I/I0),( hkl)]: 2.974 (100) (112), 1.712 (59.8) (132), 3.810 (50.6) (110), 2.702 (41.2) (022), 2.497 (38.1) (120), 1.450 (37.2) (134), 6.786 (24.9) (010), and 5.374 (24.5) (011). The mineral, which has been approved by the CNMNC under number IMA 2015122, is named in honor of Edgar Huen.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
