Table2_Gemological features of diaspore in sodra—Milas (mugla) region.docx

Diaspore, is related to bauxite in terms of its formation mechanism. Diaspore is one of the gemstone quality stones used in jewelry and jewelry making. It is possible to come across gemstones in various regions of the world. In our country, there are gemstone deposits in all regions. In these deposits, diaspore crystals are considered very valuable. Within the scope of this study, it was aimed to determine the gemological features of the diaspore formations in Sodra (Milas-Mugla) and its surroundings, as well as to determine other minerals and their formation conditions. Main oxide, trace, and rare earth element analyses were performed on seven collected samples. The classification was made using the Al2O3-SiO2-Fe2O3 triangular variation and it was determined that bauxite samples were in the “ferric bauxite” and “bauxite” areas. SEM imaging and EDS analyzes were performed on the samples and according to this result, it was determined that the samples mainly contained O, Al, and Si. The data obtained as a result of Raman Spectroscopy were matched with the device’s own data library and it was determined that the samples taken from the Sodra region were diaspore. In addition, according to the results of the FTIR analysis performed on the faceted sample taken from the Sodra region, it was seen that the samples were compatible with the reference standards and it was scientifically proven to be a diaspore crystal with gemstone quality. During the field studies carried out in the study area, diaspore crystals were encountered in the Milas-Sodra region, together with chloritoid and muscovite, within the metabauxite formations and in the altered zones close to the metabauxite limestone contact. Rock were classified as “muscovitequartzschist,” “quartzschist” with grano-lepidoblastic texture, “micaquartzschist” with lepidoblastic texture, “phyllite” with lepidoblastic texture, and “chlorite-epidote fels” with nematoblastic texture as a result of petrographic analyzes performed on the country rock samples. It is predicted that these gemstone-quality diaspore crystals can be evaluated economically.

硬水铝石（Diaspore）的形成机制与铝土矿密切相关，其为可应用于珠宝首饰制作的宝石级矿物之一。全球诸多地区均有该矿物产出，研究者所在国家的各区域亦分布有其宝石级矿床，此类矿床中的硬水铝石晶体具有极高价值。本研究旨在明确索德拉（Sodra，穆拉省米拉什）及其周边区域产出的硬水铝石矿体的宝石学特征，同时鉴定伴生矿物并解析其形成条件。研究人员对采集的7件样品开展了主量氧化物、微量元素及稀土元素测试分析；采用Al₂O₃-SiO₂-Fe₂O₃三角图解进行分类，结果显示铝土矿样品分别落入“铁质铝土矿”与“铝土矿”区域。对样品开展扫描电子显微镜（Scanning Electron Microscope, SEM）成像及能谱（Energy Dispersive Spectrometer, EDS）分析后，确认样品的主要组成元素为氧、铝及硅。将拉曼光谱（Raman Spectroscopy）测试所得数据与仪器自带数据库进行比对，确认索德拉区域采集的样品为硬水铝石。此外，对该区域采集的刻面样品开展傅里叶变换红外光谱（Fourier Transform Infrared Spectroscopy, FTIR）测试，结果显示其与参考标准谱图完全匹配，科学证实该样品为宝石级硬水铝石晶体。在研究区域开展野外调查期间，研究人员在米拉什-索德拉区域的变铝土矿矿体中，以及变铝土矿与灰岩接触带附近的蚀变带内，发现了与硬绿泥石（chloritoid）、白云母（muscovite）伴生的硬水铝石晶体。对围岩样品开展岩石学分析后，将其划分为以下类型：具花岗鳞片变晶结构的白云母石英片岩（muscovitequartzschist）、具鳞片变晶结构的石英片岩（quartzschist）与云母石英片岩（micaquartzschist）、具鳞片变晶结构的千枚岩（phyllite），以及具针状变晶结构的绿泥-帘石霏细岩（chlorite-epidote fels）。研究预测，此类宝石级硬水铝石晶体具备可观的经济开发价值。