Developing of the suitable mining techniques on deposits of chalcedony in Saricakaya (Eskisehir) and amethyst in Gugu Villiage (Balikesir)

In this thesis, Mayislar-Saricakaya (Eskisehir) chalcedony and Dursunbey-Gugu (Balikesir) amethyst deposits discussed under two main topics. The most appropriate production methods, examplary gemstone mining, have been investigated and discussed. On site studies in the fields, chalcedony, amethyst, and host-rock samples were collected, thin sections are made from this samples and then examined under a polarizan microscope, thereby the relations between gems and host rocks have revealed. On the samples, density and porosity experiments are performed; physical properties and quality of the material that will be produced are defined. Accordingly, the most appropriate mining method that was concluded is, open-pit mine. The core samples taken from the host rocks, physco-mechanic properties are determined and the single point load strength, uniaxial compressive strength, Brazilian tensile strength values are measured. Bench slope angles, height and number of benchs have been decided. Bench heights in chalcedony and amethyst open pit mines are chosen shorter than bench heights in conventional open-pit applications, so it could be possible to choose chalcedony and amethyst selectively from the host rock, to do afforestation and landscaping works easily after the completion of mining operation, to create an intact topographic image. A pilot-scale drilling-cracking operation was done in the chalcedony field and applicability of the method has been tested. It is determined that, using a material with crack feature due to expansion effect, minimizes the fractures and cracks in chalcedony nodules and increase the yield significiantly, compared to production that made by blasting.