The mineralogy, geochemistry, and suitability for ceramic applications of Akharım (Afyonkarahisar, W Turkey) kaolinitic clay

Abstract

Kaolinitic clays associated with sedimentary rocks cover widespread in the Yenikoy formation from the Akharim district, (Afyonkarahisar, W Anatolia). Due to the proximity to the ceramic industry areas such as Kutahya and Usak Province of Turkey, the clays in the Akharim district have been intensively exploited for the last few years. The Akharim kaolinitic clays were hosted by Middle-Upper Miocene-aged Yenikoy formation and divided into two parts as northeastern and southwestern via normal fault. The alteration degree increases from lower levels to surface in the NE part of deposit. Besides layered structure in their N70° W/30° SW direction and gray-beige, yellowish brown colored in SW part. This study focused on mineralogy, geochemistry, and ceramic properties of kaolinitic clays. X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis, chemical, physical, and mechanical tests were conducted on studied samples from the wall of clay quarry. Akharim clay deposits consist of mainly kaolinite and quartz. Additionally, they include smectite, biotite, feldspar, jarosite, calcite, and hematite minerals. Akharim clays are characterized with their moderate plasticity (PL = 17.07–24.09), low water absorption (3.64–9.53 wt.%), low linear shrinkage (8.08–15.55 wt.%), high bending strength (17.72–32.69 N/mm2), and ideal lightness values (L* = 46.50–82.74) and color values (a* = 4.71–29.87; b* = 14.67–28.72). These properties vary related with mineralogical and geochemical features of Akharim clays. In conclusion, Akharim clays have desired specifications for floor and wall t to their mineralogical, geochemical, and ceramic properties.