A huge gypsum miarolitic cavity has been found locatedin an antimony mineralized layer. It is an interformational bleb. Four crystallization steps are recognized for mineral crystals in the miarolitic cavity. Gypsum c...A huge gypsum miarolitic cavity has been found locatedin an antimony mineralized layer. It is an interformational bleb. Four crystallization steps are recognized for mineral crystals in the miarolitic cavity. Gypsum crystals seem to have been formed through two forms of crystallization. The data on fluid inclusions and hydrogen isotopes.show that this cavity is the product of hypergenic process, the orebeariug solution is derived from meteorie water, and the compositional material comes from the oxidized ore zone. During the formation of the miarolitic cayity, the pH-value was within the range of 4--5, i.e., weakly acidic solution, and the formation temperature less than 50℃. It can be clearly seen from the crystallization behaviour of gypsum cyrstals and mineral association that there have taken place significant changes in the pH-value of mineralization solution.展开更多
Experiments on the formation of chkalovite through reactions of beryl with aqueous solutions of Na2B4O7-·10H2O, NaHCO8 and NaOH respectively were carried out under hydrothermal conditions. Comparison of mineralog...Experiments on the formation of chkalovite through reactions of beryl with aqueous solutions of Na2B4O7-·10H2O, NaHCO8 and NaOH respectively were carried out under hydrothermal conditions. Comparison of mineralogical features was also made between chkalovites formed under different alkaline media mentioned above. The order of crystallization of coexisting minerals (albite, cancrinite, and analcite) is discussed and possible cbemical reactions involved in the formation of chkalovite suggested.展开更多
文摘A huge gypsum miarolitic cavity has been found locatedin an antimony mineralized layer. It is an interformational bleb. Four crystallization steps are recognized for mineral crystals in the miarolitic cavity. Gypsum crystals seem to have been formed through two forms of crystallization. The data on fluid inclusions and hydrogen isotopes.show that this cavity is the product of hypergenic process, the orebeariug solution is derived from meteorie water, and the compositional material comes from the oxidized ore zone. During the formation of the miarolitic cayity, the pH-value was within the range of 4--5, i.e., weakly acidic solution, and the formation temperature less than 50℃. It can be clearly seen from the crystallization behaviour of gypsum cyrstals and mineral association that there have taken place significant changes in the pH-value of mineralization solution.
文摘Experiments on the formation of chkalovite through reactions of beryl with aqueous solutions of Na2B4O7-·10H2O, NaHCO8 and NaOH respectively were carried out under hydrothermal conditions. Comparison of mineralogical features was also made between chkalovites formed under different alkaline media mentioned above. The order of crystallization of coexisting minerals (albite, cancrinite, and analcite) is discussed and possible cbemical reactions involved in the formation of chkalovite suggested.