黄铁矿中晶格金、自然金、石英包体金的分离技术及测试方法

本文以铜陵地区黄铁矿为例,对黄铁矿中晶格金、自然金、石英包体金的分离技术和测试方法进行分析,其结果可用于研究载金矿物黄铁矿中的不同状态金与成矿之间的关系。

熊耳山地区前河金矿F4金矿床矿石及矿物特征研究

前河金矿F4金矿床为构造蚀变岩型中低温热液矿床,矿石类型以原生金矿石为主,矿物种类复杂,金属矿物含量一般4%~6%,脉石矿物含量95%~97%。金矿物以裂隙金的形式为主,金粒度变化范围较大,金矿物粒度以粗粒金为主,次为中粒金,并有次显微金产出。

山西义兴寨金矿床金矿物颗粒的产出及其成矿动力学意义

山西义兴寨金矿床的金主要呈包体金和裂隙金两种产出状态。文章根据成矿地球化学动力学理论 ,论证了金元素在含矿断裂发生脆性破裂和脆_韧性扩张活动中析出的化学反应类型 ,以及受反应动力学条件的制约 ,形成矿石中金不同产出状态的规律。指出热液矿床中普遍存在的包体金为热液成矿早期阶段断裂发生脆性破裂和成矿流体沸腾 ,导致快速反应结晶的产物 ;而裂隙金和晶隙金为成矿晚期金等矿质在流体中残余富集 ,同时成矿断裂再次发生脉动破裂 ,即成矿热力学演化与有利的构造动力学因素耦合作用的结果。

黄铁矿中不同赋存状态金的测试及意义—以胶莱盆地金矿中黄铁矿为例

本文论述了黄铁矿中晶格金、自然金、石英包体金的分离技术及测试方法,它可用于研究金矿载金矿物黄铁矿中不同赋存状态金与成矿的关系。运用本方法对胶莱盆地典型金矿中主成矿阶段黄铁矿三种赋存状态的金进行了测试,发现以自然金为主,且自然金含量比例差别不大,说明盆地中的金矿可能具有相同成矿流体和环境。通过对含矿与不含矿黄铁矿中离子晶格金含量研究,进行了靶区预测验证。研究发现黄铁矿中存在石英包体金,且部分金矿中石英包体金含量较高,普通测试方法可能丢失该类金,造成样品分析结果偏低,进而出现丢矿或资源量估算不准确的现象。

金牙金矿载金矿物及金的赋存状态研究

应用电子探针、电子衍射、电子顺磁共振和化学分析等多种现代方法和手段，综合研究载金矿物的特征及金的赋存状态，认为金牙金矿中载金矿物主要是毒砂和黄铁矿，金的主要赋存形式是超显微包体金，为解决金牙金矿床难处理的原生矿石提供了科学数据资料。

铜陵花树坡铜矿床伴生金(银)赋存状态及分布规律

铜陵花树坡铜矿床伴生金以矿物态为主 ,分散态极少 ;金矿物以银金矿为主 ,金矿物粒度较细 ,全部以包体金存在 ;金的理想回收率为 52 .2 1%

甘肃老金厂金矿北金矿区矿石难浸原因研究

从北金矿区矿石性质入手,结合实际生产的情况,重点分析了北金金矿石难浸的原因,同时用实际的生产数据和试验数据证明堆浸工艺并不适合这类矿石,为该地区同类矿石的提取、资源的合理利用提供了很好的借鉴。

阜新排山楼金矿金的赋存状态

排山楼金矿赋存在蚀变糜棱岩带内,金矿化发生在三类矿石中。矿石组成成分相对简单,有用矿物为自然金和银金矿,金矿物具有成色高、粒度细的特点。其赋存形式有三种,即晶隙金、裂隙金和包体金。晶隙金兼有单体和群体两种,单体金多属中粒金和细粒金。呈不规则粒状,群体金由几粒至几十粒构成,其粒度相对偏小,在群体金附近均有黄铁矿产出。裂隙金主要以长条状、角粒状充填在黄铁矿的裂隙中,包体金则作为黄铁矿、次为黄铜矿的包体金。本矿床金矿石的金矿物以晶隙金、裂隙金为主,包体金次之,这种存在形式的金矿物对于金矿的选冶是有利的。

包金黄铁矿的细菌侵蚀特征

介绍细菌对包金黄铁矿的侵蚀过程，试验证明细菌侵蚀从黄铁矿晶体裂隙、残损及边部开始。细菌对黄铁矿的侵蚀程度取决于晶体特征及包体金所处位置。

云南东川新山含金剪切带型金矿

新山金矿属构造剪切带控制的典型金矿床,产于中元古界昆阳群美党组(Pt2m)中部变质石英砂板岩中。规模大、品位富、易采易选。矿区构造——含金剪切带与土壤地球化学金异常,是寻找该类金矿的重要标志。

Fluid inclusion and mineralization of Dafulou tin deposit in Dachang metal district, Guangxi, south China

Based on the study of the petrology, mineralogy, structural geology and fluid inclusion of the Dafulou ore deposit in the Dachang ore field, the ore deposit geology and ore-forming fluids were analyzed. It shows that there are five main hydrothermal alteration types in the Dafulou ore district, namely the silicification, carbonate, sericite, pyrite and pyrrhotite. The mineralization types are composed of the stratiform type, interlayer type and stockwork type. The ore textures present as metasomatic texture, euhedral-subhedral granular texture and solid solution texture. The ore structure consists of massive structure, dissemination structure, fine veined structure, stockwork structure and brecciated structure. Four ore types are recognized, namely the disseminated ore, dense massive ore, veinlet ore and brecciated ore. Six types of fluid inclusions are determined, i.e. the single-phase gaseous fluid inclusions, single-phase salt solution fluid inclusions, two-phase vapour-rich fluid inclusions, two-phase liquid-rich fluid inclusions, three-phase CO2-rich fluid inclusions and solid（s）-bearing fluid inclusions, all of which form in three dominant temperature scopes, 120-150, 230-270, 350-460 °C. But, the majority of them form in the high temperature environment （350-460 °C）. The tectonism plays an important role in the mineralization, which usually controls the scale, occurrence and shape of the Sn orebody. There are four types of hydrothermal fluid systems, H2O-NaCl-CaCl2, H2O-CaCl2, H2O-NaCl-MgCl2 and H2O-MgCl2. Similar to the other ore deposits in the Dachang ore field, there also exists the multiple source of ore-forming fluids. Overall, the Dafulou ore deposit should be the result of the crust-mantle interaction.

Effect of melt convection on primary dendrite arm spacing in directionally solidified Pb-26%Bi hypo-peritectic alloys

Primary dendrite arm spacing（PDAS） of α phase in directionally solidified Pb-26%Bi（mass fraction） hypo-peritectic alloys was measured by considering the effect of melt convection in cylindrical samples with different diameters.The experimental results show the measured PDAS increases with increasing diameter of the sample.At the growth velocity of 5 μm/s,its value changes from 161.5 μm for the sample with 1.8 mm in diameter to 240.4 μm for the sample with 7 mm in diameter.The strong melt convection in large diameter samples causes a high bulk alloy composition and a high concentration gradient in peritectic β phase,resulting in a larger PDAS.Simultaneously,the high concentration gradient could effectively promote the peritectic transformation,enhancing the dissolution of the thin α dendrite.

Study on fluid inclusions of Shawang gold deposit in Haiyang of Shandong

Shawang gold deposit is a large gold deposit, located in the NE margin of the Jiaolai basin, which is part of Muping-Jimo metallogenic belt in eastern Shandong. It was controlled by the footwall of Guocheng fault zone and secondary faults zone. Aiming to the fluid inclusions in Shawang gold deposit, the authors carry on petrographic, microthermometric and Raman spectroscopic component analyses. The results show that there are four-type fluid inclusions： single phase inclusions, gas-liquid two-phase inclusions, pure CO2 inclusions and three-phase inclusions containing CO2. Ore-forming fluid is characterized by low salinity （4.3%-12.6% NaC1. eqv）, low density （0.64-0.97 g/cm3 ）, medium-high temperature （280℃-320℃）, metallogenic pressure with 81-94 MPa, and metallogenic depth as 7.39-7.98 kin. The fluid experienced immiscibility of CO2-NaCl- H2O system during the metallogenic process. In combination with the analysis of hydrogen and oxygen isotopes in fluid inclusions, it is determined that the Shawang gold deposit is mesothermal vein-type, with participation of mantle-derived water and magmatic water for its genesis.

Fluid inclusion characteristics of Longmenshan copper-polymetallic deposit in Yueshan,Anhui Province,China

The types, composition and physico-chemical conditions of primary fluid inclusions were researched. The results show that the primary fluid inclusions contain vapor and liquid phase type （Type I）, daughter mineral-bearing type （Type II） and pure liquid phase type （Type III）. The compositions of vapor are mainly H20 and CO2 with a tiny amounts of CH4 and H2; the liquid phase mainly contains Mg2＋, Ca2＋, Na＋, K＋, CI- and SO]-, and w（Na＋）/w（K＋）〉l; the homogenization temperatures of the primary fluid inclusions can be divided into 190-250 ℃, 250-340 ℃ and 360-420 ℃, corresponding to the salinities of 4%-9%, 9%-14%, and 14%-20.43% （NaC1 equivalent mass fraction）, respectively. The mineralization process can be divided into three episodes： the silicatization stage, the quartz-sulfide stage, and the carbonatization stage, and all of them are associated with the ore-forming hydrothermal fluid activity. The origin of the hydrothermal fluid is from magrnatic water mainly, and later it mixes with the groundwater and meteoric water, which lead to the decrease of temperature and salinity. The decrease of salinity, temperature and pressure are the main causes of the metallogenic elements unloading and enriching in the favorable position.

Study on fluid inclusions of Qiangsheng gold deposit in Fushun of Liaoning

The Qiangsheng gold deposit belongs to quartz vein type. The fluid inclusions consist of four types： aqueous single-phase inclusions, aqueous two-phase inclusions, carbonated two-phase inclusions and carbona- ted three-phase inclusions. The fluid inclusions are characterized by low salinity （5%-9% NaCl eqv） , low density （0.66-0.72 g/cm^3 ） and medium temperature （210℃-250℃）. The pressure of ore-forming is 60-95 MPa and the metallogenic depth is about 5.49-7.56 km. During the mineralizing process, ore-forming fluid under- went fluid unmixing in CO2-H2O-NaCl system. The stable isotope resuhs indicate that the ore-forming fluids mainly generated from mantle, with the participation of a small amount of atmospheric water. Comprehensive studies have suggested that Qiangsheng gold deposit belongs to the type of mesothermal hydrotherm with mantlederived fluid participating in mineralization.

Geology and fluid inclusion of Wadi Sharis Neoproterozoic orogenic gold deposits in northwestern Yemen

The Wadi Sharis orogenic gold deposit in northwestern Yemen is related to the fault and shear zones vein at medium depth in the crust in the Neoprotcrozoic meta-sedimentary and meta-volcanosedimentary succes- sion of greenschist to amphibolite facies metamorphism. Three distinct fluid inclusion types have been identified in the gold-bearing quartz sulphide veins of the deposit： （1） type I： vapour-liquid two-phase （VH2O-LH2O ）, （2） type II ： three-phase CO2 （ VCO2 - LH2O - LCO2 ） and （3） type III： vapour-rich （LCO2 - VCO2 ） inclusions. Six analysis of individual fluid inclusion indicate the fluid inclusions comprise mainly of H2O and CO2. Forma- tion P-T conditions recorded by fluid inclusions in quartz crystals correspond to 180℃-380℃ and up to 130 MPa, as indicated by high-density CO2 bubbles （up to 0. 98 g/cm3 ） observed in some inclusions. The esti- mated crystallization pressures correspond to approximately 4-10 km of overburden, assuming a lithostatic load. The salinity ranges from 0 to 22 wt%. The deposit holds at 0.2-5 g/t Au and contains low-moderate salinity.

Geology and fluid inclusion characteristics of Qilishan gold deposit in Zhaoyuan of Shandong,China

The Qilishan gold deposit is located in the southern Zhaolai gold ore belt in the northwestern Jiaodong region.A total of seven gold ore bodies have been found in the mining area.Linglong gneissic biotite granite and the NE trending Lingbei fracture control the output and distribution of the gold deposit.The ore bodies with veined or irregular shape occur in the structural alteration zone.The ore bodies of different sizes are NE trending and SE dipping.The constituent minerals of the ores mainly include pyrite,chalcopyrite,native gold,electrum,argentite,matildite,hematite,quartz and calcite.The ores are characterized by metasomatic dissolution structure,as well as veined and brecciated structures.The ore-forming process is divided into four stages,namely quartz-,pyrite-,polymetallic-and carbonate stages.Study on fluid inclusion shows that the deposit is composed of gas-liquid two-phase inclusions （Ⅰ） and three-phase inclusions containing CO2 （Ⅱ）,and that the former dominates.The homogenization temperature is 259.6℃-373.7℃ ; the salinity of three-phase inclusions containing CO2is 5.77%-9.84% （NaCl） ; the salinity of gas-liquid two-phase inclusions is 6.58%-8.54% （NaCl） ; and the estimated ore-forming pressure is 55.2-82.2 MPa.According to the nonlinear relationship between the depth and pressure of the fluid in the fracture zone,the ore-forming depth of the Qilishan gold deposit is calculated as 5.95-7.14 km.It is preliminarily determined that the deposit is a mesophilic and hypothermal gold deposit.

Relationship between CO_2-bearing fluid and gold mineralization in Haigou gold deposit of Jilin

Haigou gold deposit is a typical orogenic gold deposit. There are a reasonable amount of fluid inclusions in the gold deposit,including three types: CO2-H2O-Na Cl inclusions,pure CO2 inclusions and Na Cl-H2 O inclusions,of which most of them are CO2-bearing inclusions. The fluid salinity is 1. 43%- 9. 08%,mainly concentrated in the range of 4. 69%- 5. 41%,the density of CO2 is 0. 69- 0. 80 g / cm3,indicating that the mineralization fluid is low-medium salinity and low density fluid. A series of studies on gold-bearing quartz vein and fluid inclusions show that there exists a positive correlation between the degree of the gold mi-neralization and the amount of CO2 in the inclusions,which means the more CO2-bearing inclusions there are,the higher the content of gold is. CO2 is mainly derived from mantle fluid,and the ore-forming fluid should be derived from mantle fluid and the crust shallow fluid. The conclusions have important denotative meaning on the metallogenic mechanism of orogenic gold deposit and the deep prospecting on metal deposit.

Geochemistry of fluid inclusions from Linglong gold deposit in Shandong,China

By means of microscopy and laser Raman spectroscopy, the authors studied the fluid inclusions in petrography. The results show that there exist three-phase CO2-bearing and two-phase aqueous inclusions in gold ore; the fluid of NaC1-H2O-CO2 system went through immiscibility in ore-forming process. Ore-forming fluids were of low salinity （0. 82%- 5.40% NaCleqv）, low density （0. 54-0.93 g/cm3 ） ; mineralization temperature were concentrated in 320℃-340℃ , with ore-forming pressure in 62-126 MPa and mineralization depth in 6.34-9.35 kin. The fluid inclusions in quartz are generally characterized by a small amount of CO2 and Na. Combined with recent results of the isotopic analysis for fluid inclusions and dating data, it was indicated that the main ore-forming fluids derived mainly from source of mantle-derived fluids with a small amount of magmatic fluid and meteoric water. The genetic type was mesothermal gold deposits involved by mantle-derived fluids.

Characteristics of the ore forming fluid from the zinc poly-metallic deposit in the Mopan mine area,Guangxi Nandan

Fluid inclusions from samples from the layered and veined mineralized belt in the Mopan mine area were studied using microscopic temperature measurements and laser Raman spectroscopy.Further studies were conducted on the nature and source of the ore forming fluid and on the mechanism of deposit formation.The results show that there are three types of inclusions that occur in both the layered and veined ore body.These are liquid inclusions,CO 2 inclusions with a liquid phase,and NaCl-H 2 O multiphase inclusions.The fluid inclusions in both the layered and veined ore bodies have similar characteristics.The ore forming fluid is strongly reducing,was exposed to low to medium temperatures,salinity,and pressures.The source of this ore forming fluid was a mix of submarine volcanic spring(blow-piping),magmatic hydrothermal jet,and underground water.