东疆红山高硫型浅成低温Cu-Au矿床氧化带钾铁矾、板铁矾、副基铁矾的首次发现及其意义

新疆哈密红山高硫化物型浅成低温Cu-Au矿床的氧化带呈漏斗状产于原生硫化物矿体的上部,延深50～60m,以硫酸盐矿物为主。X射线粉晶衍射、湿法化学和差热分析研究表明,钾铁矾、板铁矾和副基铁矾3种硫酸盐矿物均系在中国首次发现。钾铁矾湿法化学分析为:H2O6.35%,SO349.72%,Na2O0.15%,Fe2O326.00%,K2O12.47%,FeO0.25%,SiO23.25%,不溶物0.85%,CaO0.11%,总计99.15%;XRD特征谱线为:4.40(100),4.26(70),6.58(47)。板铁矾湿法化学分析为H2O26.51%,SO349.91%,Na2O0.03%,Fe2O322.52%,MgO0.01%,CaO0.03%,总计99.01%;XRD特征谱线为:9.16(100),3.29(9),4.06(8)。副基铁矾湿法化学分析为H2O24.82%,SO338.53%,Al2O30.18%,Fe2O336.10%,MgO0.02%,CaO0.04%,总计99.69%;XRD特征谱线为:5.00(100),3.11(41),5.85(39)。热分析实验进一步验证了化学分析的可靠性,并对这些硫酸盐热反应机制作了解释。该类硫酸盐矿物已作为新型资源直接制酸用于湿法炼铜,具有选矿和环保上的巨大优势。对该类硫酸盐矿物的共生组合、形成次序、形成条件的深入研究还可用来反演古环境和古气候。

Krausite, rhomboclase and parabutlerite found for the first time in the Hongshan high-S epithermal Cu-Au deposit, Xinjiang, and their significance

s:The oxidized zone of the Hongshan high-S epithermal Cu-Au deposit in the Hami area,Xinjiang,NW China,occurs as a funnel in the upper part of the primary sulfide orebody,extending downward for 50-60 m.Many supergene minerals were found by X-ray diffraction(XRD),differential thermal analysis(DTA)and thermal gravimetric analysis(TGA),of which three sulfate minerals,krausite,rhomboclase and parabutlerite,were for the first time found in China.The chemical analysis of krausite gives the following results(%):H2O 6.35,SO3 49.72,Na2O 0.15,Fe2O3 26.00,K2O 12.47,FeO 0.25,SiO2 3.25,insoluble residue 0.85 and CaO 0.11 with a total of 99.15,and its XRD analysis presents the following characteristic spectra:4.40(100),4.26(70)and 6.58(47).The results(%)of chemical analysis of rhomboclase are H2O 26.51,SO3 49.91,Na2O 0.03,Fe2O3 22.52,MgO 0.01 and CaO 0.03 with a total of 99.01;and the characteristic spectra of its XRD analysis are 9.16(100),3.29(9)and 4.06(8).The results(%)of chemical analysis of parabutlerite are H2O 24.82,SO3 38.53,Al2O3 0.18,Fe2O3 36.10,MgO 0.02 and CaO 0.04 with a total of 99.69,and its characteristic spectra of XRD analysis are 5.00(100),3.11(41)and 5.85(39).DTA further verified the reliability of these chemical data and explained the thermal reaction mechanism of these sulfates.These sulfate minerals have been used as a new type of acid resource for wet smelting of copper,showing great advantages in mineral beneficiation and environmental protection.So the paleoenvironment and paleoclimate may be deduced through an intensive study of the assemblages,sequence of occurrence and formation conditions of such sulfate minerals in the oxidation zone.