Image processing techniques (band rationing, color composite, Principal Component Analyses)
are widely used by many researchers to describe various mines and minerals. The primary aim of
this study is to use remote sensing data to identify iron deposits and gossans located in Kaman,
Kırşehir region in the central part of Anatolia, Turkey. Capability of image processing techniques is
proved to be highly useful to detect iron and gossan zones. Landsat ETM+ was used to create remote
sensing images with the purpose of enhancing iron and gossan detection by applying ArcMap image
processing techniques. The methods used for mapping iron and gossan area are 3/1 band rationing,
3/5 : 1/3 : 5/7 color composite, third PC and PC4 : PC3 : PC2 as RG B which obtained result from
Standard Principal Component Analysis and third PC which obtained result from Developed Selected
Principal Component Analyses (Crosta Technique), respectively. Iron-rich or gossan zones were mapped
through classification technique applied to obtained images. Iron and gossan content maps were
designed as final products. These data were confirmed by field observations. It was observed that iron
rich and gossan zones could be detected through remote sensing techniques to a great extent. This
study shows that remote sensing techniques offer significant advantages to detect iron rich and gossan
zones. It is necessary to confirm the iron deposites and gossan zones that have been detected for the
time being through field observations.
Ch-chalcedony is a green colored member of the quartz group of gem stones. The appearance of Ch-chalcedony is very similar to that of chrysoprase. Differently, Ch-chalsedonies have a chromium element instead of a nickel element as a trace element. Green quartz used in jewelery as a seal stone, in necklaces and rings and has been one of the most valuable quartz varieties throughout history, with its beautiful green color,more rare than other quartz varieties. The Ch-chalcedonies in the North Anatolian region is yellowish-white, brownish gray, light green to dark green in color ranging from several centimeters to one meter thick in veins and lenses in the Lower-Middle Eocene dolomitic limestones. Ch-chalcedonies are composed of fine-grained and occasionally fibrous needle-like quartz; in some examples, quartz is present together with cristobalite, tridimite and cuspidine minerals. According to geochemical investigations in Ch-chalcedonies, the main oxides that were determined are as follows: SiO2 was observed in the range of 95.86–97.81%, Fe2O3 was observed in the range of 0.61–0.91% and Cr2O3 was observed in the range of 0.125–0.168%. A trace element analysis of Ch-chalcedonies, shows their significant enrichments in: Ni, Mo, Cu, Mn, V, Cr and W, especially in the Cr (up to 705 ppm). The green color of the studied Cr-chalcedonies originates from the element chromium. Taking the possible reserves into account, the hardness, color, massive structures, mineralogical, petrographical and gemological features of Ch-chalcedonies in the region are evaluated together. It is determined that they are suitable for the production of jewelry and ornaments.