they were created in crystallizing process of vlcanic rocks. The deposit od Rudnik-feldspar originates in granitoids and products of their hydrothermal change and albitisation.
The exploitation of the deposit started in 2008, the possibilities of its use in ceramic industry are actually tested. Ther are 3 quality groups of feldspar in the deposit, the difference is predominantly in iron-content.
TThe raw material is actually processed in two main steps - the first step is mining and sorting material to the size 20-80 mm. This process is aimed on the reducing of iron content, which are concentrated in small particles of soil mixted to the feldspar rocks.
The aggregate is not crushed and is supplied in untreated form up to 120 mm in size..
Feldspar is actually used in plants for building ceramics of the LASSELSBERGER Group.
| CHEMICAL CHARACTERISTICS | |
| SiO2 | 74,58 |
| Al2O3 | 14,11 |
| Fe2O3 | 1,1 |
| CaO | 0,21 |
| MgO | 0,2 |
| K2O | 4,44 |
| Na2O | 3,30 |
| TiO | 0,16 |
| MnO | 0,01 |
| Cr2O3 | 0 |
| loss of anneal | 0,74 |
