Phase composition (XRD) 
 Description: 
Dominant crystalline phase is quartz, not possible to exclude small amount kaolinite.
 
 Chemical composition (XRF) 
| Element | Content [%] | 
 |  MgO  |  0,20  | 
  |  Al2O3  |  2,66  | 
  |  SiO2  |  92,4  | 
  |  P2O5  |  0,09  | 
  |  S  |  0,02  | 
  |  K2O  |  0,48  | 
  |  CaO  |  0,14  | 
  |  TiO2  |  0,45  | 
  |  Fe2O3  |  1,85  |