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1.
Chengdeite occurs in chromite orebodies in dunite as well as in placers in their neighbourhood. The mineral occurs as granular aggregates in association with inaglyite and in some cases occurs as graphic intergrowths with native iridium. It is opaque with a metallic lustre, colour steel-black, streak black,HM = 5.2, VHN50=452 kg/mm2, cleavage not observed, fracture not observed, strongly magnetic. Its reflection colour is bright white with a yellowish tint. It has no internal reflection, bireflectance or pleochrism, and shows isotropism.Thirteen chemical analyses were carried out by means of the electron microprobe. The mean percentages of the data obtained in the 13 analyses ares S 0.001, Fe 7.9, Ni 0.03, Co 0.03, Cu 0.83, As 0.02, Rh 0.19, Pd 0.00, Os 0.06, Ir 88.5, Ft 2.2 and Pb 0.00. The simplified formula is Ir3Fe, which requires Ir 91.17 and Fe 8.83, the total being 100.00 (% ).Five strongest lines of X-ray powder diffraction (hkl, d, I)are: 111, 2.18 (80);200, 1.89 (60); 220, 1.34 (70);311, 1.142  相似文献   

2.
Malanite was first found in veinlets of disseminated copper-nickel ores inZunhua County, Hebei Province, and then in platinum-bearing chromite ores in ShuangfengVillage, Yanshan. In the former case, malanite appears as octahedrons or dodecahedrons asso-ciated with pyrrhotite, pentlandite, sperrylite and cooperite; while in the latter case, it is massiveor present in anhedral glomerocrysts, filling in cracks of iridisite and associated with osmiride,ferrian platinum and iridisite. Malanite is steel-grey in colour, opaque with metallic lustre andblack streaks and brittle with no magnetism. H_M=5.0, VHN_(20)=417kg/mm~2, cleavage {111}sometimes observed. The calculated density is 7.57g/cm~3. The reflective colour is white with alight green tint. Internal reflections are not observed. This mineral is isotropic, showing nobireflection or reflection pleochroism in air. By means of electron microprobe analysis, the em-pirical formula (based on 7 atoms) is expressed as (Cu_(0.93)Fe_(0.06))_(∑0.99)(Pt_(1.03)Ir_(0.66)Rh_(0.04)Pd_(0.03)Co_(0.20)Ni_(0.03))_(1.99)S_(4.03) or (Cu_(0.95)Fe_(0.07))_(∑1.02)(Pt_(1.37)Ir_(0.45)Co_(0.11)Rh_(0.08))_(∑2.01)S_(3.97). Five strongestlines (hkl, d, I) of X-ray powder diffraction data of malanite are 311,2.98(6); 400,2.48(5);333, 1.90(7); 440, 1.75(10); 731, 1.29(5). It was known on the basis of X-ray powder diffractiondata that malanite is cubic, and the space group is Fd3m with α=0.9940nm, V=0.9821(3)nm~3 and Z=4. The type material of malanite is deposited at the Geological Museum of China(GMC)s  相似文献   

3.
The Polar Urals region of northern Russia is well known for large chromium (Cr)-bearing massifs with major chromite orebodies, including the Centralnoye I deposit in the Ray-Iz ultramafic massif of the Ural ophiolite belt. New data on platinum (Pt)-group elements (PGE), geochemistry and mineralogy of the host dunite shows that the deposit has anomalous iridium (Ir) values. These values indicate the predominance of ruthenium–osmium–iridium (Ru–Os–Ir)-bearing phases among the platinum-group mineral (PGM) assemblage that is typical of mantle-hosted chromite ores. Low Pt values in chromites and increased Pt values in host dunites might reflect the presence of cumulus PGM grains. The most abundant PGM found in the chromite is erlichmanite (up to 15 μm). Less common are cuproiridsite (up to 5 μm), irarsite (up to 4–5 μm), and laurite (up to 4 μm). The predominant sulfide is heazlewoodite, in intergrowth with Ni–Fe alloys, sporadically with pentlandite, and rarely with pure nickel. Based on the average PGE values and estimated Cr-ore resources, the Centralnoye I deposit can be considered as an important resource of PGE.  相似文献   

4.
Listwanite from the Luobusa ophiolite,Tibet,forms a narrow,discontinuous band along the eastern part of the southern boundary fault. We undertook a detailed petrographic and geochemical study to understand the mineral transformation processes and the behaviour of major and trace elements during listwanite formation. Three alteration zones characterized by distinct mineral components and texture are recognized and,in order of increasing degree of alteration,these are: zoneIII is rich in serpentine minerals; zoneII is rich in talc and carbonates; and zoneI is mainly composed of carbonates and quartz. Geochemical data for the three alteration zones show significant modification of some major and trace elements in the protolith,although some oxides show linear correlations with Mg O. Gold mineralization is recognized in the Luobusa listwanite and may signify an important target for future mineral exploration. Gold enrichment occurs in both zoneI and zoneIIand is up to 0.91 g/t in one sample from zoneI. We show that CO2-rich hydrothermal fluids can modify both the occurrence and composition of chromite grains,indicating some degree of chromite mobility. Low-Cr anhedral grains are more easily altered than high-Cr varieties. The compositions of chromite and olivine grains in the listwanite suggest a dunite protolith.  相似文献   

5.
A new mineral species, named naquite(FeSi), is found in the podiform chromitites of the Luobusha ophiolite in Qusong County, Tibet, China. The detailed composition is Fe 65.65, Si 32.57 and Al 1.78 wt%. The mineral is cubic, space group P213. The irregular crystals range from 15 to 50 μm in diameter and form an intergrowth with luobusaite. Naquite is steel grey in color, opaque, with a metallic lustre and gives a grayish-black streak. The mineral is brittle, has a conchoidal fracture and no apparent cleavage. The estimated Mohs hardness is 6.5, and the calculated density is 6.128 g/cm3. Unit-cell parameters are a 4.486 (4) ?, V 90.28 (6) ?3, Z=4. The five strongest powder diffraction lines [d in ? (hkl) (I/I0)] are: 3.1742 (110) (40), 2.5917(111) (43), 2.0076 (210) (100), 1.8307 (211) (65), and 1.1990 (321) (36). Originally called ‘fersilicite’, the species and new name have now been approved by the CNMNC (IMA 2010–010).  相似文献   

6.
Magnesioferrite, a rare metasomatic mineral, was discovered for the first time in China from the Qinlou Au (Fe, Cu) magnesian skarn deposit, Sanpu, Huaibei, Auhui Province, and the Mulonggou Fe (Mo, Cu) magnesian skarn deposit, Luonan County, Shaanxi Province. In this paper, the geological setting, mineral associations, chemical composition, some physical properties, X-ray powder diffraction data and infrared spectroscopy of magnesioferrite and magnesiomagnetite are discussed. Magnesioferrite contains 17.66%-13.48% of MgO. Its main associated minerals are clinohumite, chondrodite, serpentine,, calcite and magnesiomagnetite. The density of magnesioferrite is 4.537-4.720, reflectances in percent are: 17.8-18.1, hardness is 838-900 kg/mm2, and the cell parameter a0 = 8.371-8.379 A. A systematic study of the magnesioferrite-magnesiomagnetite-magnetite series suggests that along with the increase of magnesioferrite molecules in the mineral, the density, reflectances and cell parameters decrease corresponding  相似文献   

7.
张宝贵 《地球化学》1977,(2):147-158
Discussion has been given to the geology and origin of a certain chromite deposit from a viewpoint of migmatization. 47 chromite orebodies have been discovered in this area. All of them, variously shaped as irregular lens, chambers, kidneys,etc., occur in migmatite, showing dear-cut contacts with the latter. Mineralogical composition of these deposits are exceedingly simple, composing mainly of chromium phlogopitc and chromite and, to the less extent, of pyrite, chalcopyrite, galena,rosite aaad etc. The pre-existing chromite deposit, which is magmatic in origin, is decply altered by migmatization, eventually giving rise to metamorphosed chromite deposits as are seen at present day.  相似文献   

8.
Chrome phlogopite, [K(Mg,Cr,Al),(AlSi8O10)(F,OH)2], occurs in a metamorphous chromite deposit in Honan, central China. Chemical analyses, optical and X-ray powder data indicate that it is a new subspecies of phlogopite. Chemically, chrome phlogopite is characterized by relatively high Cr2O3 concentration. The emerald color of this mineral is ciosely related to its Cr2O3 content, which ranges from 3.51 to 8.66%.  相似文献   

9.
We describe the new mineral species titanium,ideally Ti,found in the podiform chromitites of the Luobusha ophiolite in Tibet,People’s Republic of China.The irregular crystals range from 0.1 to 0.6 mm in diameter and form an intergrowth with coesite and kyanite.Titanium is silver grey in colour,the luster is metallic,it is opaque,the streak is grayish black,and it is non-fluorescent.The mineral is malleable,has a rough to hackly fracture and has no apparent cleavage.The estimated Mohs hardness is 4,and the calculated density is 4.503 g/cm3.The composition is Ti 99.23-100.00 wt%.The mineral is hexagonal,space group P63 /mmc.Unit-cell parameters are a 2.950(2),c 4.686(1),V 35.32(5) 3,Z = 2.The five strongest powder diffraction lines [d in(hkl)(I/I0)] are: 2.569(010)(32),2.254(011)(100),1.730(012)(16),1.478(110)(21),and 0.9464(121)(8).The species and name were approved by the CNMNC(IMA 2010–044).  相似文献   

10.
A new mineral, jichengite ideally 3CuIr2S4·(Ni,Fe)9S8, was found as a constituent of placer concentrates at a branch of the Luanhe River, about 220 km NNE of Beijing. Its associated minerals are chromite, magnetite, ilmenite, zircon, native gold, iridium, ferrian platinum and osmium. The placer is distributed at places around ultrabasic rock, which hosts chromite orebodies, from which PGM originated. Jichengite occurs commonly as massive or granular aggregates. No perfect morphology of jichengite was observed. It is steel gray and opaque with metallic luster and black streak. It has a Mohs hardness of 5, VHN (d) μm 21.65, Hm 4.465, Hv = 268.1 N/um2. It is brittle and weakly magnetic. Cleavage {010} is rarely observed. No fracture was observed. Density could not be measured because of its too small grain size. Density (calc.) is 7.003 g/cm3. Reflect light is reddish-brown, without internal reflections. Anisotropism is distinct with grayish or yellowish white in crossed nicols and bluish violet-copper red in uncrossed nicols. Jichengite shows weak pleochroism and strong bireflectance. The reflectance values in air at the Standard Commission on Ore Mineralogy wavelengths are: 38.9, 34.3 at 470 nm, 38.9, 34.5 at 546 nm, 39.1, 35.3 at 590 nm, 39.2, 36.8 at 650 nm, parallel-axial extinction. The six strongest lines in the X-ray powder-diffraction pattern [d in ?, (I), (hkl)] are: 3.00 (100) (116), 2.80 (50) (205), 2.48. (50) (208), 1.916 (40) (2, 1, 10), 1.765 (60) (220), 1.753 (50) (2, 0, 16). Five chemical analyses carried out, yielding the following results: S 25.76 (25.49-5.97), Fe 10.03 (9.78-10.31), Co 0.78 (0.75-0.81), Ni 12.48 (12.32-12.85), Cu 4.77 (4.69-4.83), Ir 46.98(46.14-47.89), sum 100.80wt%, which produced a formula (Cu1.556Fe0.976)2.532(Ir5.063S10.126)·(Fe2.7451Ni4.404Co0.273)7.422S6.517. The ideal formula is X10Ir5S17.5, which was calculated by single crystal structure analyses, where X = Cu(II) + Fe(II) + Ni(II) + Co(II). The single crystal data were collected using a diffractometer with Mo Ka radiation and a graphite monochromate. The crystal system is trigonal with space group R3m and unit cell parameters a=7.0745(14) ?, c=34.267(10) ? (The superstructure not found), and the final R Indices [with 564 observed reflections, I>2sigma (I)] are R1=0.0495, wR2=0.1349. The specimens are deposited in the Geological Museum of China.  相似文献   

11.
於祖相 《矿物学报》1998,18(2):134-137,T001
富碲马营矿产在纯橄榄岩铬矿体中。在铝矿石及矿体附近的砂矿中均可找到。呈粒状自形结构,直径0.01~0.15mm。与硫铱矿(IrS2)、双峰矿、高台矿、马营矿及(Fe,Ni)9Cu3Ir6S20等紧密共生。有的呈脉状,宽0.1~0.2mm,长1.2mm。金属光泽。不透明,钢灰色,粉末黑色。HM=3.7。VHN50=161kg/mm2(范围132~215kg/mm2)。无解理。无断口。性脆。计算密度为12.2g/cm3。反射色亮白带淡黄色调,内反射无,均质性,双反射与反射多色性无。5个电子探针分析数据平均为(%):Cu0.3,Te32.9,Ir34.7,Pt2.7,Bi28.2,总量98.9。实验式根据原子数3计算为:(Ir(0.92)Pt(0.92)Cu(0.01));(1.00)Bi(0.68)Te(1.31)。简化后的理论式为Ir(Te,Bi)2,而(Ir:Bi:Te=3:2:4)。6条富碲马营矿是强X射线衍射hki、d、I为:210,2.89(60);311,1.95(100);511,1.246(70);520,1.204(60);440,1.145(60);533,0.9891(60)。根据X射线粉晶指标化求得马营矿为等轴晶系,空间群:Pa3,a=0.6486(4)um,V=0.2729nm3,Z=4。富碲马营矿是本文作者对马营矿研究的继续与补充。  相似文献   

12.
Yixunite and damiaoite Were found in a cobalt- and copper-bearing platinum ore vein of a contact metasomatic deposit. The chief ore minerals are bornite, chalcopyrite, magnetite and carrollite. The platinum minerals include moncheite, sperrylite, daomanite, cobalt malanite and cooperite. Yixunite and damiaoite occur as immiscible globules, 1.0 to 2.0 mm in diameter. Yixunite is always in the central part of a globule. It is opaque with metallic lustre, bright white colour and black streak. HM = 5.8; VHN50 = 634 kg/mm2 (573-681 kg/ mm2); insoluble in HCl, HNO3, HF or H3PO4; no cleavage; no magnetism. Density is hard to measure because of small grain size. Calculated density = 18.21 g/cm3. Reflective colour is bright white with a yellowish tint. Isotropic. The mean analytical results (ranges) (%) are: Pt 82.8 (81.8-83.6), In 16.4(15.6-17.1) and total 99.2. The empirical formula (based on 4 atoms) is Pt2.993 In1.007 . The five strongest lines of X-ray diffraction (hkl, d,I) are 111, 2.30 (100); 200, 1.99 (  相似文献   

13.
新矿物双峰矿—铱的二碲化物   总被引:2,自引:1,他引:2  
於祖相 《矿物学报》1994,14(4):322-326,T002
双峰矿产在纯橄榄岩体铬矿体中。在铬矿石及矿体邻近的砂矿中均可找到,呈块状聚集体或板片状与硫铱矿、锇自然铱矿紧密共生。直径0.5 ̄0.2mm,脉状的宽0.05 ̄0.10mm,长0.5 ̄1.0mm。金属光泽。条痕黑色。H(M)3。VHN20108kg/mm^2(平均)。解理:(0001)完全。性脆。计算密度为10.14g/cm^3。反射色:亮黄白带蓝色调。内反射无。非均质性中等,偏光色为淡蓝或淡黄。双  相似文献   

14.
於祖相 《矿物学报》1998,18(1):12-16
铂双峰矿产在纯橄榄岩铝矿体中。在铝矿石及矿体邻近的砂矿中均可找到。呈块状聚集体或板片状自形晶,与疏钻矿、含锇自然铱紧密共生。脉状的宽20~301μm,长400~500μm,一般10μm×20μm。金属光泽。条痕黑色。HM=3.05。VHN20=92kg/mm2(平均)。{0001}解理完全。性脆。计算密度为10.21g/cm2。反射色;亮黄白带淡蓝色。内反射无。非均质性中等,偏光色为淡蓝或淡黄。双反射或反射多色性在空气中或油中均未见。5个电子探针分析数据平均(wt%):Cu0.2,Te57.2,Ir24.5,Pt17.2,Bi0.4,总量99.5。实验式为:(IR0.57Pt0.39Cu0.01)0.98(Te1.99Bi0.01)2.00。简化理论式为(11,Pt)Te2。4条最强X射线粉晶衍射线hkl,d,I为:101,2.87(100);102,2.10(70);110,1.98(60);103,1.58O(50)。根据X射线粉晶数据进行指标化,获得铂双峰矿晶胞数据:三方晶系,P3ml,a=0.3973(5),c=0.5315(5)um,V=0.0727nm3,Z=1。铂双峰矿是笔者对双峰矿研究的继续与补充。  相似文献   

15.
云南乐红铅锌矿床氧化带中异极矿的矿物学特征及其意义   总被引:7,自引:0,他引:7  
云南乐红铅锌矿床氧化带十分发育,呈细脉或葡萄状产于氧化矿石中的白色矿物曾被认为是菱锌矿,笔者对该矿物作了物理、光学性质,化学发,X射线衍射,红外光谱及失重和差热分析研究,确定其为异极矿。其晶体化学式为Zn3.98(Si2.01Al0.01)2.02O7(OH)2.03.0.88H2O晶胞参数a=0.8380(4)nm,b=1.0718(7)nm,c=0.5125(6)nm。对异极矿矿物学特征的全面  相似文献   

16.
於祖相 《地质学报》1997,71(4):336-339
长城矿产在铬铁矿体及临近矿体的铂砂矿中。呈块状聚集体或细脉状,分布在硫铱矿的边缘并交代它。不透明,金属光泽,钢灰色,条痕黑色。莫氏硬度H_M=3.7,显微硬度VHN_(20)=165kg/mm~2。均质性,无解理。计算密度D_(calc.)=11.96g/cm~3。7个电子探针分析的平均化学成分(%):S 7.2,Cu 0.3,Te 0.4,Ir 41.2,Pt 2.8,Bi 47.2,总量99.1。简化的化学式为IrBiS。5条最强X射线粉晶衍射线(hkl,d,I)为:210,2.75(70);211,2.51(60);311,1.860(100);440,1.090(50);600,1.027(50)。X射线粉晶衍射图谱与马营矿相似。进行对比后,长城矿可以指标化为等轴晶系、空间群P2_13。由X射线粉晶衍射线求得α=0.6164(4)nm,V=0.2342nm~3,Z=4。  相似文献   

17.
田澍章  陈静渝 《矿物学报》1990,10(4):382-384
黑铋金矿产于广东封开蚀变花岗岩中,主要伴生矿物有自然金、自然铋、碲铋矿。该矿物的颜色为银白色,在反光镜下反射色为灰色带黄绿色色调,经能谱分析结果Au=65.28%,Bi=34.72%,计算分子式为Au_(1·995)Bi_(1·000),反射率测定为51.5(405mm),48.9(436nm),50.9(480nm)53.7(644nm),51.9(656nm),42.1(700nm)。对该矿物还作了X射线粉晶衍射分析。  相似文献   

18.
四方铜金矿产于新疆玛纳斯县清水河上游萨尔达拉含铂基性-超基性岩体中。岩体主要为暗绿色蛇纹石化斜辉辉橄岩,岩石化学成分多数为正常系列,少数为铝过饱和系列。岩体长9公里,宽140米,是一个向南倾斜的单斜岩墙。岩体侵入到泥盆系头苏泉组的黑灰色粉砂质板岩中。外接触带仅几十厘米到1米左右宽,以绿泥石化、绿帘石化、蛇纹石化为主,其次是碳酸岩化。内接触带有1米多宽,以蛇纹石化、透辉石化、透闪石化为主,个别地段有阳起石、透闪石软玉。  相似文献   

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