Advertisement

Mineralogical, geochemical, and gemological characteristics of silicic gemstone in Aydıncık (Yozgat-Turkey)

  • Zeynel BaşıbüyükEmail author
Original Paper
  • 136 Downloads

Abstract

There are chalcedony and amethyst formations in two fields in Aydıncık-Yozgat (West of Aydıncık District, Keşlik area and Southwestern of Hacıilyas). The gemstones in this region have been formed within the gaps and cracks of the brecciated rocks of the fault zone in altered andesites. Chalcedony and amethyst are either present in the form of crack fillings from a few millimeters to 10 cm in width, or in the form of generally oval pore fillings reaching a few centimeters to 40 cm in diameter. The chalcedony is composed of 0.1-mm–centimeter-thick bands parallel to each other in varying tones ranging from light blue/white to dark blue to reddish brown, and in some points in the central part of this banded structure are large crystalline quartz and amethysts. Chalcedony occurs as kidney—banded and geodesic forms as cryptocrystalline and macrocrystalline. The altered volcanic rock with brecciated texture, which hosts chalcedony and amethyst occurrences in both regions, is the altered andesite. Petrographic examinations carried out from chalcedony and amethysts indicated that gemstones composed of fine-coarse grained quartz have microcrystalline texture in the rim zones and have macrocrystalline texture toward the core. XRD analysis of chalcedony and amethyst with different colors and crystal grain sizes revealed that gemstones in the region were composed of large and microcrystalline quartz. When amethyst, blue chalcedony, and reddish brown chalcedony were compared to white transparent quartz, there was a significant increase in the amounts of Fe2O3 and Al2O3, and metal elements (Mo, Cu, Pb, Zn, Ni, Co, Mn, Cr) in the case of amethyst and reddish brown chalcedony. The visible reserves of chalcedony and amethysts in the region, their dimensions and varying color range, and large-grained texture and physical properties show that the chalcedonies and amethyst formations can be used as gemstones. Use of these formations as gemstones also makes a significant contribution to the regional economy.

Keywords

Gemology Geochemistry Chalcedony Amethyst Gemstone 

Notes

Acknowledgements

Some part of this study was carried out within the scope of the project of PYO-MÜH.4001.15.002 (Akbudak et al., 2016) supported by Ahi Evran University Scientific Research Projects Coordination Unit. We would like to extent our thanks to the project researchers and Ahi Evran University Scientific Research Projects Coordination Unit, which provided financial support to carry out this work.

Funding information

Some part of this study was carried out within the scope of the project of PYO-MÜH.4001.15.002 supported by the Ahi Evran University Scientific Research Projects Coordination Unit. We would like to extend our thanks to the project researchers and Ahi Evran University Scientific Research Projects Coordination Unit, which provided financial support to carry out this work.

References

  1. Adekeye JI, Cohen AJ (1986) Correlation of Fe+4 optical anisotropy, Brazil twinning and channels in the basal plane of amethyst quartz. Appl Geochem 1:153–160CrossRefGoogle Scholar
  2. Akbudak İK, Gürbüz M, Ulus Ü, Başıbüyük Z (2016) Aydıncık (Yozgat) Kalsedonların Mineralojik, Jeokimyasal ve Gemolojik İncelemesi. Ahi Evran Üniversitesi Bilimsel Araştırma Projesi, No: PYO-MÜH.4001.15.002, 55 sGoogle Scholar
  3. Akbudak KI, Basıbüyük Z, Gürbüz M (2018) Yozgat “Aydıncık” kalsedon-ametist oluşumlarının mineralojisi-petrografisi ve ekonomikliliğinin incelenmesi. Dicle Üniversitesi Mühendislik Fakültesi Mühendislik Dergisi 9(1):313–324Google Scholar
  4. Balitsky VS, Machina IB, Mar AA, Shigley JE, Rossman GR, Lu T (2000) Industrial growth, morphology and some properties of Bi-colored amethyst–citrine quartz (ametrine). J Cryst Growth 212/1:255–260CrossRefGoogle Scholar
  5. Barry TI, Moore WJ (1964) Amethyst, optical properties and paramagnetic resonance. Science 144:289–290CrossRefGoogle Scholar
  6. Çevik N (2009) Yozgat-Yerköy-Belkavak Köyü Civarı Kalsedon ve Ametist Oluşumlarının İncelenmesi, Ankara Üniversitesi, Fen Bilimleri Enstitüsü, Yüksek Lisans Tezi, Jeoloji Mühendisliği Anabilim Dalı, 110s., AnkaraGoogle Scholar
  7. Çevik N, Sayılı İS (2010) Yozgat-Yerköy-Belkavak Kalsedon– Kuvars ve Ametist Oluşumlarının Jeolojik, Mineralojik ve Jeokimyasal Özellikleri, 2. Uluslararası Katılımlı Mücevher – Takı Tasarımı ve Eğitimi Sempozyumu, 575Google Scholar
  8. Flörke OW, Graetsch H, Mıehe G (1983) Crystalstructure and microstructure of Chalcedony. Fortschr Mineral 61(1):62–63Google Scholar
  9. Flörke OW, Graetsch H, Röller K, Martin B, Wirth R (1991) Nomenclature of micro-and non-crystalline silica minerals. Neues Jahrbuch für Mineralogie, Abhandlungen 163:19–42Google Scholar
  10. Frondel C (1978) Characters of quartz fibers. Am Mineral 63:17–27Google Scholar
  11. Frondel C (1982) Structural hydroxyl in chalcedony (type B quartz). Am Mineral 67:1248–1257Google Scholar
  12. Gislason SR, Heaney PJ, Veblen DR, Livi KJT (1993) The difference between the solubility of quartz and chalcedony: the cause? Chem Geol 107:363–366CrossRefGoogle Scholar
  13. Görür N, Tüysüz O, Celal Şengör AM (1998) Tectonic evolution of the central Anatolian basins. Int Geol Rev 40(9):831–850CrossRefGoogle Scholar
  14. Graetsch H (1994) Structural characteristics of opaline and microcrystalline silica minerals. Rev Mineral Geochem 29(1):209–232Google Scholar
  15. Hatipoğlu M, Dora OÖ (2000) Ankara Agatının mineralojisi ve bantlı yapının kökeni. Yerbilimleri Dergisi 22:1–12Google Scholar
  16. Hatipoğlu M, Babalık H, Chamberlain SC (2010a) Gemstone deposits in Turkey. Rocks & Minerals 85(2):124–133CrossRefGoogle Scholar
  17. Hatipoğlu M, Helvacı C, Kibar R, Çetin A, Tuncer Y, Can N (2010b) Amethyst and morion quartz gemstone raw materials from Turkey: color saturation and enhancement by gamma, neutron and beta irradiation. Radiation Effects and Defects in Solids 165(11):876–888CrossRefGoogle Scholar
  18. Hatipoğlu M, Kibar R, Çetin A, Can N, Helvacı C, Derin H (2011) Spectral, electron microscopic and chemical investigations of gamma-induced purple color zonings in amethyst crystals from the Dursunbey-Balıkesir region of Turkey. Radiation Effects & Defects in Solids 166(7):537–548CrossRefGoogle Scholar
  19. Hatipoğlu M, Chamberlain SC, Kibici Y (2013) Characterization of the Sündikendağı deposit of moganite-rich, blue chalcedony nodules, Mayıslar–Sarıcakaya (Eskişehir), Turkey. Ore Geol Rev 54:127–137CrossRefGoogle Scholar
  20. Kretz R (1983) Symbols for rock-forming minerals. Am Mineral 68:277–279Google Scholar
  21. Kumbasar I, Aykol A (1993) Mineraloji, İstanbul Teknik Üniversitesi Kütüphanesi, Sayı: 1519, İstanbulGoogle Scholar
  22. MTA (2002) 1/500.000 Türkiye Jeoloji Haritası, Maden Tetkik ve Arama Genel Müdürlüğü, AnkaraGoogle Scholar
  23. Özsert E (2009) Aydıncık (Yozgat) Yöresinin Tersiyer (Lütesiyen) İstifinin Bentik Foraminiferleri. Çukurova Üniversitesi, Fen Bilimleri Enstitüsü, Yüksek Lisans Tezi Jeoloji Mühendisliği Anabilim Dalı, AdanaGoogle Scholar
  24. Selim H (2014) Türkiye’nin Değerli Ve Yarı Değerli Mücevher Taşları, İstanbul, 102sGoogle Scholar
  25. Üstündağ A, İnceöz M (1999) Zile (Tokat) batısında Uzunköy çevresinin stratigrafisi, 42/1, 69–83Google Scholar

Copyright information

© Saudi Society for Geosciences 2018

Authors and Affiliations

  1. 1.Faculty of Engineering – Architecture, Department of Geological EngineeringAhi Evran UniversityKirşehirTurkey

Personalised recommendations