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Crystal structure refinement of suolunite and its significance to the cement techniques

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Chinese Science Bulletin 1999年第23期44卷 2125-2130页

作者： Zhesheng Ma nicheng shi Guodong Mou Libing Liao China Univ Geosci Xray Lab Beijing 100083 Peoples R China

Based on the crystal structure refinement, the arrangement and characteristics of the double tetrahedra of Si-O backbone of suolunite have been precisely clarified. The double tetrahedra are isolated, and the orientations of the closely adjacent double tetrahedra are perpendicular to each other, which results in the poor cleavage and high hardness of suolunite. Com-

关键词： suolunite crystal structure C-S-H gel cement manufacturing techniques.

Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 39-43页

作者： shi nicheng and Liao Libing Beijing Graduate School, China University of Geosiences, Beijing Beijing Graduate School China University of Geosiences Beijing

This paper mainly deals with the point groups and single forms of octagonal quasicrystals and the description of one-dimensional quasilattice. The authors present a new sequence for describing the arrangement of quasiperiods in one-dimensional quasilattice. The first ten numbers of quasiperiods of this sequence are 1, 1, 2, 5, 12, 29, 70, 169, 408 and 985. The arrangement of quasiperiods in the first five steps are a, b, ab. babab and babababbabab. Seven p(?)nt groups and nine single forms for the octagonal system have been deduced, They are as follows: Point groups: 8.8m, 82, 8/m, 8/mmm, 8 and 82m; single forms: octagonal prism, dioctagonal prism. octagonal pyramid. dioctagonal pyramid. octagonal dipyramid, dioctagonal dipyramid, octagonal scalenohedron, dioctagonal scalenohedron and octagonal trapezohedron. Besides seven point groups and nine single forms for the dodecahegonal system have also been deduced.

关键词： Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

Titanium, Ti, A New Mineral Species from Luobusha, Tibet, China

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1275-1280页

作者： FANG Qingsong BAI Wenji YANG Jingsu RONG He shi nicheng LI Guowu XIONG Ming MA Zhesheng Institute of Geology CAGS X-ray Diffraction Laboratory China University of Geosciences

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 P6flmmc. Unit-cell parameters are a 2.950 （2） ~, c 4.686 （1） A,V 35.32 （5） A3, Z = 2. The five strongest powder diffraction lines [d in A （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）.

关键词： Titanium new mineral species Ti chromitite Luobusha ophiolite Tibet

Yarlongite:A New Metallic Carbide Mineral

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 52-56页

作者： shi nicheng BAI Wenji LI Guowu XIONG Ming FANG Qingsong YANG Jingsui MA Zhesheng RONG He X-ray Laboratory China University ofGeosciences Beijing 100083 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Yarlongite occurs in ophiolitic chromitite at the Luobusha mine （29°5′N 92°5′E, about 200 km ESE of Lhasa）, Qusum County, Shannan Prefecture, Tibet Autonomous Region, People＇s Republic of China. Associated minerals are： diamond, moissanite, wiistite, iridium （＂osmiridium＂）, osmium （＂iridosmine＂）, periclase, chromite, native iron, native nickel, native chromium, forsterite, Cr-rich diopside, intermetallic compounds Ni-Fe-Cr, Ni-Cr, Cr-C, etc. Yarlongite and its associated minerals were handpicked from a large heavy mineral sample of chromitite. The metallic carbides associated with yarlongite are cohenite, tongbaite, khamrabaevite and qusongite （IMA2007-034）. Yarlongite occurs as irregular grains, with a size between 0.02 and 0.06 mm, steel-grey colour, H Mohs： 5^1/2-6. Tenacity： brittle. Cleavage：（0 0 1） perfect. Fracture： conchoidal. Chemical formula：（Cr4Fe4Ni）29C4, or （Cr,Fe,Ni）29C4, Crystal system： Hexagonal, Space Group： P63/mc, a = 18.839（2） A, c = 4.4960 （9） A, V = 745.7（2） A^3, Z = 6, Density （calc.） = 7.19 g/cm3 （with simplified formula）. Yariongite has been approved as a new mineral by the CNMNC （IMA2007-035）. Holotype material is deposited at the Geological Museum of China （No. Ml1650）.

关键词： yarlongite new mineral metallic carbides ophiolite luobusha Tibet

Luobusaite:A New Mineral

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 656-659页

作者： BAI Wenji shi nicheng FANG Qingsong LI Guowu XIONG Ming YANG Jingsui RONG He Institute of Geology Chinese Academy of Geological Sciences Baiwanzhang Road 26 Beijing 100037 X-ray Laboratory China University of Geosciences （Beijing） Xueyuan Road 29 Beijing 100083

A group of mantle minerals including about 70-80 subtypes of minerals are discovered from a podiform chromitite in Tibet, China. Recovered minerals include diamond, coesite, moissanite, wustite, Fe-silides and a new mineral, luobusaite. All of these minerals were hand-picked from heavymineral separates of the podiform chromitite in the mantle peridotite of an ophiolite. The grains of luobusaite are as host mineral with inclusions of native silicon or as an intergrowth with native silicon and Fe-Si phase. Luobusaite occurs as irregular grains, with 0.1-0.2 mm in size, consisting of very finegrained aggregates. The mineral is steel-grey in color, metallic luster, and opaque. The empirical formula （based on 2 for Si） is Fe0.83Si2, according to the chemical compositions of luobusaite. X-ray powder-diffraction data： orthorhombic system, space group Cmca, a = 9.874 （14） A, b = 7.784 （5） A, c= 7.829（7） A, Z=16.

关键词： new mineral luobusaite chromitite ophiolite Tibet

A New Three-Dimensional Superstructure in Bafertisite

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1028-1035页

作者： LI Guowu~*,XIONG Ming,shi nicheng and MA Zhesheng Crystal structure laboratory,National Laboratory of Mineral Materials,China University of Geosciences (Beijing),Beijing 100083,China Crystal structure laboratory National Laboratory of Mineral Materials China University of Geosciences (Beijing) Beijing 100083 China

A new superstructure was found in bafertisite[(Ba;Na;);(Fe;Mn;Mg;);TiO [(Si;Ti;Al;Cr;);O;](OH;F;Cl;);]from Donghai County,Jiangsu Province,*** occurrence of the superstructure reflections were observed by single crystal diffraction using a SMAR APEX *** a;,b;and c;axis directions revealed extra weak reflection spots of the *** apparent 2a,2b and 2c superstructure is monoclinic with unit cell a=10.6502（15） A,b= 13.7233（19）A,c=21.6897（3）A,α=90°,β=94.698（3）°,γ=90°,space group Cm,Z=*** c;extra weak reflections are ignored,the secondary supercell gave a cell a=10.6548（15）A,b=13.7284（19）A,c = 11.6900（17）A,α=90°,β=112.322（28）°,γ=90°,space group Cm,Z=*** basic subcell was obtained by ignoring all extra weak reflection spots and gave:a=5.3249（17）A,b=6.8669（22）A,c=10.8709（36） A,α=90°,β=94.740（62）°,γ=90°,space P2;/m,Z=*** superstructure has been refined to R = 0.063 for 7805[R;= 0.0266]unique reflections I>2δ（I）.The structure consists of an octahedra（O） sheet sandwiched between two heteropolyhedral（H） *** sheets consist of Ti-octahedra and twin tetrahedral disilicate groups[Si;O;].The O sheet comprises（Fe,Mg）O;*** large Ba cation is located in the interlayer *** refined structure shows Fe,Mg are partly *** shifting of the TiO;octahedron and SiO;tetrahedron sites in the sheet may be a consequence of the superstructure.

关键词： bafertisite superstructure crystal structure layered titanium silicate

Mineralogy and crystal structure determination of Mg-fillowite

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Science China Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , shi nicheng 1 & YE Danian 2 1. China University of Geosciences, Beijing 100083, China 2. Institute of Geology, Chinese Academy of Sciences, Beijing 100029, China China University of Geosciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2Ca(Mn4Mg2Fe)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, China. It is of the trigonal lattice, with space group R-3, unit cell a=1.5143(3) nm, c=4.3191(2) nm, V=8.5736 nm3, Z = 18. The R-factor of the determination accuracy is R (I > 2σ ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 720 atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Structure refinement of astrophyllite

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Science China Earth Sciences 2001年第6期44卷 508-516页

作者：马喆生李国武施倪承周湖云叶大年 D.YU.PUSHCHAROVSKY China University of Geosciences Beijing 100083China Southwest Institute of Technology Mianyang 621002China China University of Geosciences Beijing 100083China Institute of Geology Chinese Academy of SciencesBeijing100029China Department of Geology Moscow State UniversityMoscow 119899Russia

The crystal structure of astrophyllite K2Na(Fe, Mn, Mg,□)7[Ti2(Si4O12)2|O3](OH, F)4 has been refined. The dimensions of the triclinic unit cell are: a = 0.5359(2) nm,b = 1.1614(4) nm, c = 1.1861(4) nm, α= 113.16(2)°, β= 103.04(2)°,γ= 94.56(2)°,V = 0.6495(5) nm3, Z= 1, space group P1, R=0.057 for 5308 reflections |Fo|>3σ|Fo|. According to structural and compositional differences the monoclinic astrophyllite K2NaNa(Fe, Mn)4Mg2Ti2[Si4O12]2(OH)4(OH, F)2 and astrophyllite should be considered as two different mineral species. Astrophyllite, monoclinic astrophyllite, bafertisite and lamprophyllite contain heteropolyhedral sheets which topologically are related with Si, O sheets of mica where one or several SiO4 tetrahedra are replaced by TiO n polyhedra. Therefore this heterophyllotitanosilicate series represents a kind of functional substitution in inorganic crystals.

关键词： astrophyllite crystal structure functional substitution

CRYSTAL STRUCTURE OF D'ANSITE

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Chinese Science Bulletin 1987年第7期32卷 478-481页

作者：施倪承马喆生 Beijing Graduate School of Wuhan Geological College Beijing Graduate School of Wuhan Geological College'ansite is a rare mineral in solt deposits. R. Gorgey described its existence briefly in Hal solt deposit in 1909. But he did not name it nor give its mineralogical data. H. Autenrieth and G. Braune got the crystal of d'ansite by synthesis in 1958 and its physical properties were determined. He named this mineral "d'ansite". Its existence in nature was confirmed when the mineral was discovered in a drill core of the Tertiary strata in the Jianghan Plain and was first investigated by Zheng Jinping in 1972. Later Qu Yihua et al. reported the results of their study on d'ansite.

D’ansite is a rare mineral in solt deposits. R. Gorgey described its existence briefly in Hal solt deposit in 1909. But he did not name it nor give its mineralogical data. H. Autenrieth and G. Braune got the crystal of d’ansite by synthesis in 1958 and its physical properties were determined. He named this mineral 'd’ansite'. Its existence in nature was confirmed when the mineral was discovered in a drill core of the Tertiary strata in the Jianghan Plain and was first investigated by Zheng Jinping in 1972. Later Qu Yihua et al. reported the results of their study on d’ansite.

关键词： Tertiary strata briefly drill plain isotropic camera idealized picture itself