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Copyright of Mineral Resources Management / Gospodarka Surowcami Mineralnymi is the property of Mineral & Energy Economy Research Institute of the Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Şenkaya chrysoprase is a gemstone and can be found near the Turnalı village located in the west-northwest of Şenkaya (Erzurum) county in the uplifted Kırdağ of Northeast Anatolia of Turkey. Chrysoprase only found in Şenkaya County and known with the same name commercially in Turkey is a light-dark green and cryptocrystalline structure gemstone encountered in the Örükyayla Mélange. Samples were collected from the field for defining mineralogical-petrographical, XRD, XRF, ICP-MS, optical cathodoluminescence microscopy (OCLM), FTIR-Raman and stable isotopic properties of Şenkaya chrysoprase. According to mineralogical and petrographic examination, Şenkaya chrysoprase has generally heterogeneous color distribution in macroscale and has 5 Mohs mineral hardness. Microquartz filling (10%-15%) was seen in the microexamination with serpentine as main component with partly massive opal type silica. The XRF analyses indicate that many samples had high SiO2 values (91.45-94.38 wt%). As a result of trace elements, rare earth elements, Au-Pt group analyses using ICP-MS, Ni (167-387 ppm) and Co (12.57-74.78 ppm) values are quite remarkable. In the OCLM studies, few metallic minerals which could produce CL and could spread CL in different colors due to some trace activator elements were observed. Oxygen isotopic (d18OV-SMOW) values obtained from three chrysoprase samples are 24.8‰, 27.7‰ and 30.63‰, respectively and mean formation temperature is 96-99 oC. [ABSTRACT FROM AUTHOR]

Copyright of Adalya is the property of Koc University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The corundum is found in the rocks of the Berit metaophiolite in Eastern Anatolia, near Doğanşehir a province of Malatya. Metaophiolitic rocks consist mainly of garnet metagabbro, granulite, amphibolite, mylonitic amphibolite, garnet amphibolite, amphibole schist, pyroxenite, mylonitic pyroxenite, orthopyroxenite, harzburgite, serpentinized dunite and diorite units. Corundum occurrences are mostly found in pyroxenites, amphibolites, peridotites and granulites. Their colors change in range between reddish pink, pink and light pink. They are usually in structure of translucent, vitreous and sometimes cracked. They are seen scattered or clustered together inside the rocks in which they are found. The size of their crystals ranges from 0.5 cm to 10 cm and their euhedral crystals are observed in pseudohexagonal form. As a result of the petrographic examinations, it was observed that pyroxene, amphibole, garnet and plagioclase minerals accompanied with the corundum. The samples of the rocks containing the corundum has qualifications which will be as an object of gemstone and ornament by means of cutting and shining. Large specimens of corundum can be processed alone. Samples, being as scattered and small granules inside the rock can be processed together with the host rock. In the processed samples, it was obtained patterns like the samples of corundum with zoisite which were in great demand in the world gemstone market. [ABSTRACT FROM AUTHOR]