广西大厂地区黑云母花岗岩中电气石的化学组成及其对岩浆热液演化的指示

广西大厂地区笼箱盖黑云母花岗岩与区内晚白垩世锡多金属成矿作用在时空上密切相关。岩相学特征表明,笼箱盖黑云母花岗岩中的电气石可以分为三类:1)浸染状电气石; 2)石英-电气石囊; 3)电气石-石英脉。本文利用电子探针和激光剥蚀等离子体质谱系统测定三种不同产状电气石的化学组成。分析结果显示,三种产状的电气石均具有高的Fe/(Fe+Mg)和Na/(Na+Ca)比值,主体属于碱基亚类铁电气石。浸染状电气石为岩浆晚期结晶,其Fe/(Fe+Mg)比值变化于0. 85～0. 94,随着岩浆分异,电气石逐渐富集Li、F、Fe和Sn等元素。与浸染状电气石相比,石英-电气石囊中早阶段电气石具有低的Fe/(Fe+Mg)比值,高的V、Co和Sr含量,可能反映了岩浆演化晚期出现的不混溶富硼熔/流体对早期黑云母和长石的交代作用,从而使囊中早阶段电气石继承部分被交代矿物的化学组成特征;石英-电气石囊中晚阶段电气石的化学组成变化较大(如Li、F、Mg、Al、V、Fe和Zn),与热液成因电气石的推论一致。与浸染状和囊状电气石相比,石英脉中的电气石具有高的Fe/(Fe+Mg)和Na/(Na+Ca)比值;微量元素组成与囊状电气石相似。就成矿元素锡而言,三种产状的电气石均具有相对高的锡含量,与其他地区锡成矿花岗岩中电气石的成分特征相似。但是,从岩浆晚期到热液阶段,大厂地区电气石的锡含量并没有显著升高,可能反映了早期岩浆热液流体对熔体锡有限的萃取作用。     

Chemical composition of tourmaline from the Yunlong tin deposit, Yunnan, China: implications for ore genesis and mineral exploration

Summary ?The Yunlong tin deposit is located in the northern part of the Lancangjiang metamorphic zone of the Sanjiang Tethys orogen series in western Yunan province of China. It consists of vein-type cassiterite ores, which are mainly hosted in migmatites of Caledonian age. Abundant tourmaline is associated with the ores, quartz–tourmaline veins and barren migmatized gneiss and migmatites. A detailed electron microprobe study has been carried out to document the chemical compositions of tourmaline from this deposit. The results exhibit a systematic compositional change that might be used as tracer for ore genesis and in prospecting for tin mineralization. Tourmalines from the ore bodies are dravite with Fe/(Fe + Mg) ratios of 0.09 ∼ 0.31 and Ca/(Ca + Na) ratios of 0.03 ∼ 0.40. These tourmalines are also rich in chromium (up to 0.74 wt% Cr₂O₃) and tin (up to 0.42 wt% Sn). In contrast, tourmalines from the barren migmatites are mostly schorl with Fe/(Fe + Mg) ratios of 0.38 ∼ 0.94 and Ca/(Ca + Na) ratios of 0.00 ∼ 0.14. Tourmalines from quartz–tourmaline veins that occur between ore bodies and the migmatites show intermediate compositions, i.e., Fe/(Fe + Mg) = 0.09 ∼ 0.59, Ca/(Ca + Na) = 0.01 ∼ 0.22. It is suggested that the Mg-rich nature of the tourmaline can be used as an exploration tool in this region to target tin mineralization, because the tourmalines show increasing Mg contents and are more dravitic when approaching the ore bodies. It is likely that the formation of the Yunlong tin deposit was related to migmatitic-hydrothermal processes. The high Mg and Cr contents in tourmalines from the ore bodies were probably derived from the local meta-sedimentary and meta-volcanic rocks of the Precambian Chongshan Group rather than from the granites in the region. Received December 28, 2000; revised version accepted January 25, 2002     

藏南过铝花岗岩中电气石的矿物化学特征及成因意义

讨论了藏南过铝花岗岩中电气石的地质产状、矿物学和矿物化学特征。结果表明:(1)在以氧原子数为24.5计算的化学式中,电气石的(Fe+Mg)/Mg比值在2.32~5.37之间,指示花岗岩和伟晶岩中的电气石均为黑电气石系列,而且属镁电气石—铁电气石系列中的较富铁电气石的成员;(2)电气石的FeO/(FeO+MgO)值高达0.70~0.89,与贫Li花岗岩接近,Al-Al50Fe50-Al50Mg50图解和Fe-Mg-Ca图解投点均位于贫Li花岗岩区,属于贫Li花岗岩有关的电气石;(3)TiO2-MnO/CaO-MgO/FeO三元图解可判定属于第Ⅰ类,即MgO和FeO含量同步消长,且较贫Mg富Fe,而MnO和TiO2含量为异步消长,这与电气石的FeO/(FeO+MgO)值所反映的性质相同;(4)地质产状、矿物学及矿物化学揭示的成因信息表明藏南过铝花岗岩中的电气石为酸性侵入体岩浆期后热液成因。     

加拿大Sullivan超大型Pb-Zn-Ag矿床中几个指示成矿环境的特征矿物研究

加拿大Sullivan矿床是世界上最典型的SEDEX型Pb-Zn-Ag矿床。对该矿床中产出的几个特征矿物,如硼矿物电气石,富氯的方柱石和黑云母,富钡的钾长石和白云母,及富锰的石榴子石、绿泥石、碳酸盐和钛铁矿进行了研究。指出这些矿物的存在反映了该矿床产出的物理化学环境。提出成矿流体可能淋滤了深部存在的非海相蒸发岩层,层状硫化物矿石可能形成于海底高盐度热卤水池中。     

Tourmalinites from the Eastern Sierras Pampeanas, Argentina

In the eastern Sierras Pampeanas, Central Argentina, tourmalinites and coticules are found in close association with stratabound scheelite deposits in metamorphic terranes. In Sierra Grande (Agua de Ramón and Ambul districts) and Sierra de Altautina, tourmalinites are associated with stratabound scheelite deposits related to orthoamphibolites. In the Pampa del Tamboreo area, tourmalinites are located in biotite schists stratigraphically related to acid to intermediate metavolcanic rocks and scheelite-bearing quartzites.The mineral chemistry and boron isotopic compositions of tourmalinite-hosted and vein-hosted tourmalines are investigated. Overall, the tourmalines belong to the dravite-schorl series and are generally aluminous; Fe/(Fe+Mg) ranges from 0.33 to 0.85, Al/(Al+Fe+Mg) from 0.66 to 0.76 and the amount of X-site vacancy (0.12–0.48) indicates significant foitite components. Their boron isotopic compositions (δ¹¹B) are from −24.0‰ to−15.0‰.Similar mineral chemistries and boron isotopic values for tourmaline in tourmalinites related to stratabound scheelite mineralisation and in tungsten-bearing quartz veins suggest a common source for the boron and probably the tungsten. The field, chemical and isotopic relationships are consistent with tungsten and boron in quartz-vein deposits being remobilised from stratabound scheelite and tourmalinite, dominantly by liquid-state transfer associated with regional shear zones. Tungsten and boron in the original sedimentary sequence (now meta-exhalites) are ascribed to volcanogenic exhalations.     

The geological setting of tourmalinite at Rum Jungle,N.T., Australia — genetic and economic implications

Tourmalinite is a common rock type associated with Proterozoic strata-bound mineral deposits. Although common, it is often difficult to recognise in the field, leading to misidentification. It occurs as a conformable banded quartz-tourmaline lithological unit comprising at least 15% and as much as 50% of the rock. At Rum Jungle, tourmalinite occurs within the oldest sediments (arenites and magnesites) as distinct lenses, as facies equivalents of quartz-magnetite units and mafic schists (tuffs?) and distal equivalents of polymetallic sulfides. Distinct layering, slump folding, rip-up clasts and the association with diagenetic pyrite suggest a sedimentary environment. Enechelon fracturing of the fine-grained, light green tourmaline crystals spectacularly supports pre-deformation formation. The crystals are optically and chemically zoned parallel to the c axis, with irregular growth lamellae width — which supports a pre-regional metamorphic origin. Analyses show the tourmaline to be the Mg-rich variety “dravite”. Most tourmalinites are interpreted as subaqueous marine deposits. It is more likely that they form in lacustrine, shallow water, evaporitic environments, particularly continental rifts. Suitable B-bearing fluids can be generated by hotspring activity and mobilized by CO₂-rich fluids. Association with chemical sediments suggests tourmalinites also have a chemical sediment precursor. Ample evidence at Rum Jungle supports the notion of a continental rift environment, which was the site of deposition of fluvial arenites and alkaline, evaporitic lake sediments. Localised hot-spring activity contributed B-bearing fluids which precipitated chemical sediments according to the pertaining pH, temperature etc. Diagenetic alteration produced the tourmalinite now present. These tourmalinites are comparable to those of similar age elsewhere e.g. Sullivan, Broken Hill. They can be genetically modelled upon Recent borate concentrations, all of which occur in continental rift environments.     

山西省中条山铜矿田电气石与电气石岩的研究

本文通过对中条山铜矿田电气石和电气石岩地质产状、岩相学和矿物学、矿物化学等特征的研究，指出本区有三种成因类型的电气石：（１）北峪酸性侵入体岩浆期后热液成因电气石；（２）中条群地层中变质热液形成的电气石；（３）赋矿岩石和近矿围岩中热液蚀变电气石。第（３）类电气石具有特征的产状、矿物化学和矿物共生组合标型，是重要的找矿标志     

柿竹园矿床大理岩型锡矿石工艺矿物学研究

大理岩型锡矿石产于燕山早、中期千里山花岗岩与中、上泥盆统灰岩的外接触带。矿石呈细脉、网脉浸染状,锡矿物有:锡石、黄锡矿,富钛尼日利亚石、尼日利亚石和木锡矿,脉石矿物绿帘石、石榴石、电气石、萤石、方解石及磁黄铁矿等亦含锡,锡主要呈锡的浊立矿物存在,占总锡量的89.78％,其中锡石锡占总锡量的80.01％,其次有呈类质同象形式存在的锡,在绿帘石、石榴石、电气石等矿物中以Sn~(4+)取代Fe~(3+),这类锡占总量的8.33％。工艺矿物学研究表明,该类锡矿石以“贫”、“细”、“杂”为特征。锡不仅十分分散,而且品位偏低,矿石矿物组合及镶嵌关系复杂、相互包裹,紧密连生;锡矿物粒度微细,粒径一般为0.2～0.01mm,部分为<0.0l～0.002mm,是一种难选的锡矿石类型。通过锡的回收试验,采用选冶联合工艺流程,预测锡的最佳回收率可达50％以上。     

Tourmalinites from the Golden Dyke Dome,Northern Australia

Tourmalinites occur at five stratigraphic levels within the low metamorphic grade multiply deformed Lower Proterozoic metasediments and metavolcanics of the Golden Dyke Dome. The geological setting, exhalite associations, sedimentary structures and tourmaline chemistry all preclude a granitic origin. Tourmalinite derived from the isochemical metamorphism of an exhalite comprising silica and tourmaline. Tourmalinite and other exhalites are hosted by carbonaceous pelitic metasediments and were deposited in deeper basinal areas. The ore fluid was probably dolerite-heated seawater which leached a thick pile of argillaceous sediments and acquired metals and boron by leaching. The first and second increase in geothermal gradient produced tourmalinite, the third produced auriferous tourmalinite and iron formations with tourmalinite and exhalative Pb-Zn deposits forming during the period of maximum geothermal gradient. More tourmalinite formed during the subsequent decline in geothermal gradient. Tourmalinites are regarded as B-rich iron formations which can be the host for or associated with exhalative deposits of Au and base metals.     

A staurolite-talc assemblage in tourmaline-phlogopite-chlorite schist from northern Victoria Land,Antarctica, and its petrogenetic significance

Staurolite and corundum are found as inclusions in tourmaline in a talc-phlogopite-chlorite-albite chist near Mount Bernstein (71°37S, 163°07E), northern Victoria Land, Antarctica. These inclusions are interpreted as relics of a staurolite-talc-corundum-chlorite assemblage that was stable during an early stage in the metamorphic cycle and subsequently armored by tourmaline, probably during the middle stage. Pressures and temperatures during the middle stage are estimated to be 650–700°C and 5.5–6.4 kbar. The transition from the early to the middle stage represents a roughly isothermal decrease in pressure of 2–3 kbar. During a late retrograde stage (T=300–370°C, P=3–5 kbar), staurolite was partly replaced by a muscovitic aggregate containing clinozoisite, pumpellyite, and margarite.The staurolite is unusually Si-poor (26.77, 25.85 weight % SiO₂ or 7.275, 7.091 Si per formula unit for 46 oxygens anhydrous), Al-rich (58.00, 57.85% Al₂O₃, 18.579, 18.702 Al), low in divalent cations (Fe+Mg+Mn+Zn=3.301, 3.560) and magnesian (atomic Mg/(Mg+Fe)=0.42, 0.40). Ion microprobe analysis of the first grain indicates about 0.2% Li₂O (0.219 Li) is present. The following substitutions are proposed to explain the unusual chemistry of this staurolite (crystallographic site notation of Smith 1968, in bold letters): Al(Si)+Al(Al(3A,B))Si(Si)+Fe(Fe), Li(Fe)+Al(Al(3A,B))2 Fe(Fe), and 2 Al(Al(3A,B)) 3 Fe(Fe).According to a pressure-temperature diagram constructed by the method of Schreinemakers for the model system FeO-MgO-Al₂O₃-SiO₂ (H₂O in excess), the talc-staurolite assemblage should be stable only in quartz-free rocks at temperatures near 700° C and pressures of 8 kbar or more. The rarity of the staurolite-talc assemblage even in Mg-Al-rich rocks metamorphosed at the appropriate pressure-temperature conditions is attributed to the appearance of anthophyllite or, in Na₂O-bearing rocks, gedrite. Orthoamphibole-cordierite and orthoamphibolekyanite assemblages with chlorite or corundum are incompatible with staurolite-talc±albite. In rocks lacking corundum and formed at pressures above the stability limit of cordierite, staurolite-talc may be metastable relative to orthoamphibole-kyanite, while in corundum-bearing rocks, staurolite-talc may appear under certain conditions, possibly at higher water activities than the orthoamphibole-kyanite assemblage.     

The Loulo gold and tourmaline-bearing deposit

The stratabound polymorph Loulo gold deposits and occurrences were discovered in sedimentary rocks of the Early Proterozoic Birimian Formation, in the Kéniéba region of SW Mali. Early work showed reserves in the Loulo-0 and Loulo-3 deposits of 28 t of gold in ore averaging 4.43 g/t Au, to depths of 140 m; recent drilling has found mineralization to at least 300 m depth. Early tourmalinization of the sedimentary host rock is indicated by reworked tourmalinite pebbles in non-tourmalinized hanging-wall rocks. Mineralization, restricted to highly tourmalinized zones, occurs as: (a) pre-D1 (deformation) disseminated pyrite with micron-size inclusions of gold particles; (b) syn-/late-D2 stockworks with minor disseminated sulphides and native gold. Gold in the sulphides is small (10–40 gm), and occurs at pyrite-crystal edges, filling cracks and/or as inclusions. Post-D2 stockwork mineralization derived from the pre-D1 one that was emplaced with tourmaline, as is indicated by the small differences between pre-D1 and post-D2 sulphur isotopes, as well as by the type of quartz vein that indicates an almost closed system. In West Africa, the pre-D1 mineralization of Early Birimian age represents the first major introduction of gold into the Proterozoic. It attributes a major metallogenic role to the tourmalinized sandstone that indicates crustal accretion in West Africa during the Early Proterozoic. Editorial handling: D.D. Klemm     

广西热水沉积成矿作用的基本特征

详细叙述了广西热水沉积型矿床的成矿时代、空间分布和控矿环境，指出主要的矿产种类有锡、铅、锌、锑、汞、金、铜、钨、锰、铁、磷、重晶石及黄铁矿。其成矿时代为早元古代、晚元古代、早古生代、晚古生代及中生代，以泥盆纪为最重要的成矿时代；矿床在空间上主要分为桂北晚古生代裂陷锡-多金属成矿带及桂西南泥盆纪裂陷锰-重晶石-黄铁矿成矿带，次为桂东南早古生代裂陷铅-锌-多金属成矿带、桂中-桂北泥盆纪走滑断陷铅-锌-重晶石黄铁矿成矿带及桂西北早中三叠世裂陷金矿成矿带，此外还有桂北-桂东元古宙裂陷铁-锡-重晶石成矿带；控矿构造环境为裂谷构造，成矿受裂陷槽及区域性同沉积断裂控制；控矿沉积环境主要为台沟相带，次为局限-半局限台地相带、开阔台地相带、生物礁相带及海槽相带。并指出广西的热水沉积岩主要有硅质岩、电气石岩、层状矽卡岩及重晶石岩。     

云南个旧卡房锡矿田花岗岩黑云母矿物化学特征及其成岩成矿意义

黑云母作为花岗岩中含量最高的暗色矿物,其成分特征对指示岩石成因与成矿起着重要作用。云南个旧卡房锡多 金属矿床的形成与花岗质岩浆活动密切相关,卡房花岗岩包含有大量黑云母,通过电子探针测试方法,对该花岗岩中的 黑云母成分进行了系统的研究。结果显示,黑云母为富铁黑云母,具有富硅、铁、铝、钾、钛,贫锰、镁、钙、钠等特 征,含铁指数为0.67~0.83。黑云母的成分特征暗示其结晶温度为500~708 ℃,结晶压力为202~538 MPa,对应的结晶深度为 7.64~20.35 km,表明卡房花岗岩形成于中低温环境、属于中深成相。综合研究认为,卡房锡矿田花岗岩具有高铁指数以及 氧逸度由高到低变化趋势等特征是锡成矿的有利条件,可以作为在本区寻找锡矿的重要标志。     

Stability of the assemblage orthopyroxene-sillimanite-quartz in the system MgO-FeO-Fe2O3-Al2O3-SiO2-H2O

The stability of coexisting orthopyroxene, sillimanite and quartz and the composition of orthopyroxene in this assemblage has been determined in the system MgO-FeO-Fe₂O₃-Al₂O₃-SiO₂-H₂O as a function of pressure, mainly at 1,000° C, and at oxygen fugacities defined mostly by the hematite-magnetite buffer. The upper stability of the assemblage is terminated at 17 kbars, 1,000° C, by the reaction opx+Al-silicate gar+qz, proceeding toward lower pressures with increasing Fe/(Fe+Mg) ratio in the system. The lower stability is controlled by the reaction opx+sill+qz cord, which occurs at 11 kbars in the iron-free system but is lowered to 9 kbars with increasing Fe/(Fe+Mg). Spinel solid solutions are stabilized, besides quartz, up to 14 kbars in favour of garnet in the iron-rich part of the system (Fe/(Fe+Mg)0.30). Ferric-ferrous ratios in orthopyroxene are increasing with increasing ferro-magnesian ratio. At least part of the generally observed increase in Al content with Fe²⁺ in orthopyroxene is not due to an increased solubility of the MgAlAlSiO₆ component but rather of a MgFe³⁺AlSiO₆ component. The data permit an estimate of oxygen fugacity from the composition of orthopyroxene in coexistence with sillimanite and quartz.     

Mineral resources of Southern Africa in time-stratigraphic perspective

The tectono-stratigraphic setting of mineral deposits in southern Africa is reviewed with reference to 5 outline maps portraying stages in the evolution of the subcontinent.The Early and Middle Archaean Eras are characterized by deposits of Cr, Au and Fe; the Late Archaean by Au, U and Ni. In the Early Proterozoic the intrusion of vast mafic complexes supplied Cr, Ni, Pt, Cu and V-Fe ore, while sedimentary basins received Fe, Mn, Cu, Pb and Zn in marginal seas. The Middle Proterozoic was a singularly poor metallogenic Era, producing only pegmatite minerals and a variety of Cu deposits. The Late Proterozoic is typified by widespread occurrence of Cu, Pb, Zn and local U in geosynclinal belts; pegmatite minerals formed on a large scale in rejuvenated basement. Carbon is the most important element of Phanerozoic deposits, accounting for the fossil fuels besides appearing as diamond in kimberlite. It also contributed to the precipitation of sandstone-type U. Post-Gondwana morphology and climate effected further surface concentration and dispersal of minerals.     

Geology,mineral chemistry and tourmaline B isotopes of the Córrego Bom Sucesso area,southern Serra do Espinhaço,Minas Gerais,Brazil: Implications for Au–Pd–Pt exploration in quartzitic terrain

The Palaeo-Mesoproterozoic metasiliciclastic rocks of the southern Serra do Espinhaço, Minas Gerais, Brazil, are host to historically important alluvial deposits of diamonds and gold. Detrital gold grains often comprise Au–Pd–Pt intermetallic compounds, with low Ag contents, which contain inclusions of tourmaline and titaniferous hematite (up to ~ 6 wt.% TiO₂). The latter minerals connect the alluvial mineralisation to the rutile–hematite–quartz veins and tourmalinisation observed in the quartzitic country rocks of the alluvial gravel. The quartzite (Sopa-Brumadinho Formation of lacustrine to fan-deltaic origin) is affected by pervasive B metasomatism with F-bearing tourmaline replacing the recrystallised quartz fabric. The tourmaline belongs to the alkali group, with Mg/(Mg + Fe) and X/(X + Na) ratios in the ranges from 0.5 to 0.7 and 0.18 to 0.29, respectively, where X represents vacancies in the X site. Boron-isotopic values of tourmaline vary from ~ 1 to − 10.4‰ δ¹¹B. The B-isotope range, in conjunction with the Na–Mg-rich tourmaline composition, and the widespread occurrence of tourmalinite in the Sopa-Brumadinho Formation suggest a derivation from non-marine evaporitic brines. Brines are capable of transporting otherwise immobile Ti and explain, under oxidising conditions, the fractionation of Ag from Pd to precipitate palladiferous gold with extremely high Pd/Ag ratios. Zirconium-in-rutile and Ti-in-quartz temperatures for a variety of hematite-rich veins suggest episodic vein emplacement over a temperature range from around 500 °C to ~ 350 °C. Cross-cutting relationships and episodic vein emplacement indicate a late-Brasiliano age.     

南极洲地质矿产概况

南极洲主要呆分为东南极地盾及西南极中新生代褶皱带两大构造单元,两者之间的横贯南极山脉具有过渡性质,由基底与盖层构成。基底为由元古宙及下古生界组成的双构造层基底;盖层则由泥盆系－二叠系组成。侏罗纪中期,冈瓦纳大陆开始裂解。白垩纪晚期,南极大陆向南移动,并于中新世早期到达现在位置。东南极的帮产以铁为主,其主要类型是前寒武纪条带状铁建造。横贯南极山脉产出与罗斯期（奥陶纪）花岗岩有关的Ｕ－Ｔｈ矿化,与侏罗     

The Pre-Sinian Basement and Mineralization on the Western Margin of the Yangtze Paraplatform

The pre-Sinian basement on the southwestern margin of the Yangtze paraplatform consists of threemetamorphic rock series of different ages. Being products of different tectonic events and environments, theydiffer markedly in original rock sequences, metamorphism. tectonic style and characteristics of granitoids andmineral deposits. The Late Archean Kangdian cration mainly comprises the Kangding and Julin Groups with ametamorphic age of nearly 2500 Ma. They are supracrustal rocks dominated by mafic volcanics enclosed introndhjemitic rocks The craton is believed to represent a granite-greenstone terrane of Late Archaean age.There occur mineral deposits such as graphite and kyanite deposits of metamorphic origin, muscovite depositsin pegmatites and gold quartz veins in gneissic granites, banded hornblende-magnetite mineralization and cop-per and zinc mineralizations related to felsic volcanics. Large V-Ti-bearing magnetite deposits were also formedin the mafic. ultramafic stratiform intrusions emplaced on the margins of the craton during the MiddleProterozoic. Copper and nickel deposits are found in several ultramafic intrusions. Extending in a north-southdirection, the Proterozoic mobile belt consists mainly of the Early Proterozoic Hekou Group and MiddleProterozoic Huili and Kunyang Groups. and they are thought to be accumulations in a Proterozoic rift troughor aulacogen. During the Early Proterozoic, the rift trough was characterized by intense volcanism and pres-ence of iron ore deposits of volcano-magmatic type, iron-copper deposits of exhalative-sedimentary type. TheMid-Late Proterozoic of the rift trough mainly witnessed the formation of sedimentary stratiform copper de-posits and submarine sedimentary iron deposits. In the wake of the emplacement of the Jinningian andChengjiangian granites in the Late Proterozoic, skarn-type tin and tin-iron ore deposits were formed.     

Mineral Geochemical Compositions of Tourmalines and Their Significance in the Gejiu Tin Polymetallic Deposits, Yunnan, China

Abstract: The Gejiu tin polymetallic deposits are located in the southeastern part of Yunnan Province in China. A detailed electronic microprobe study has been carried out to document geochemical compositions of tourmalines from the deposits. The results indicate a systematic change of mineral geochemical compositions, which might be used as a mineral geochemical tracer for post-magmatic hydrothermal fluid, basin fluid and their mixture. The tourmalines from granite are schorl with Fe/(Fe+Mg) ratios of 0.912-1.00 and Na/(Na+Ca) ratios of 0.892-0.981. Tourmalines as an inclusion in quartz from the ore bodies are dravite with Fe/(Fe+Mg) ratios of 0.212-0.519 and Na/ (Na+Ca) ratios of 0.786-0.997. Tourmalines from the country rocks are dravite with Fe/(Fe+Mg) ratios of 0.313-0.337 and Na/(Na+Ca) ratio of 0.599-0.723. Tourmalines from cassiterite-tourmaline veins that occur in crannies within the country rocks show distinct optical zoning with alternate occurrence of dravite and schorl, Fe/(Fe+Mg)=0.374-0.843, Na/(Na+Ca)=0.538-0.987. It suggests that schorl in granite and dravite in carbonatite are related to magmatic fluid and basin fluid respectively. When magmatic fluid rose up and entered into crannies of the country rocks, consisting mainly of carbonatite, basin fluid would be constantly added to the magmatic fluid. The two types of fluid were mixed in structural crannies of the sedimentary basin accompanied with periodic geochemical oscillations to form material records in chemical composition zonings of tourmalines.