Dumańska-Słowik Magdalena, Powolny Tomasz, Sikorska-Jaworowska Magdalena, Gaweł Adam, Kogut Lucyna, Poloński Krzysztof
Faculty of Geology, Geophysics and Environmental Protection, Department of Mineralogy, Petrography and Geochemistry, AGH-University of Science and Technology, 30 Mickiewicza av., 30-059 Krakow, Poland.
Faculty of Geology, Geophysics and Environmental Protection, Department of Mineralogy, Petrography and Geochemistry, AGH-University of Science and Technology, 30 Mickiewicza av., 30-059 Krakow, Poland.
Spectrochim Acta A Mol Biomol Spectrosc. 2018 Mar 5;192:6-15. doi: 10.1016/j.saa.2017.11.005. Epub 2017 Nov 7.
Agates from Płóczki Górne hosted by Permian basaltic rocks are predominantly made of length-fast chalcedony, and subordinately megaquartz and quartzine. Moganite occurs in traces mainly in transparent, outer, darker regions of white-grey coloured agates. Silica matrix of agates comprises a wide variety of solid inclusions represented by celadonite, plagioclases, hematite, goethite, barite, calcite, heulandite-clinoptyloite, nontronite-saponite, and Mn-dioxides (ramsdellite). Mineral phases are locally accompanied by black aggregations of carbonaceous matter, which gives a Raman signature of disordered carbon. These organic components were probably deposited from a hydrothermal fluids at low-temperature conditions and originated from sedimentary rocks found in the surrounding area of Płóczki Górne. The abundance of various SiO phases, mineral inclusions as well as various micro-textures (colloform, comb, feathery, and jigsaw-puzzle) in agates resulted from physicochemical fluctuations of SiO-bearing mineralizing solutions at various stages of these gems formation. Agates from Płóczki Górne formed during post-magmatic stage of basaltic host rocks evolution. Not only were the hydrothermal fluids enriched in silica, but also they contained other elements such as Na, Ca, Al, Mg, Mn, Fe, Ba, SO, and CO, which were mobilized from host rocks or surrounding area.
产自普沃茨基戈尔内且赋存于二叠纪玄武岩中的玛瑙主要由长度不变的玉髓组成，次要成分是巨石英和石英岩。杆沸石主要出现在灰白色玛瑙透明的外部较深区域。玛瑙的硅质基质包含多种固体包裹体，有绿脱石、斜长石、赤铁矿、针铁矿、重晶石、方解石、片沸石-斜发沸石、绿脱石-皂石以及锰的氧化物（羟锰矿）。矿物相在局部伴有黑色碳质物质聚集，其拉曼光谱显示为无序碳。这些有机成分可能是在低温条件下由热液流体沉淀而成，源自普沃茨基戈尔内周边地区的沉积岩。玛瑙中各种二氧化硅相、矿物包裹体以及各种微观结构（钟乳状、梳状、羽毛状和拼图状）的丰富多样，是这些宝石形成各阶段含硅成矿溶液物理化学波动的结果。普沃茨基戈尔内的玛瑙形成于玄武岩宿主岩石演化的岩浆后期阶段。热液流体不仅富含硅，还含有从宿主岩石或周边地区迁移而来的其他元素，如钠、钙、铝、镁、锰、铁、钡、硫酸根和碳酸根。
