REFSAN POTASSIUM FELDSPAR
REFSAN POTASSIUM FELDSPAR
RAW MATERIALS AND OXIDES

REFSAN POTASSIUM FELDSPAR (5130)

Brand : REFSAN
Price : 10,60TL
ÇOKALAZÖDE BOYA

 

POTASH FELDSPAR

One of the most important materials for medium and high-temperature ceramic glazes. Potash feldspars are often not as pure and white as soda spars. A feldspar is typically referred to as 'potash' if there is significantly more potassium than sodium (typically there will be 2-5% Na2O). If the amounts are closer to equal they have termed potash-soda feldspars (or vice versa). Of course, real potash feldspars also have small amounts of CaO, MgO, Fe2O3, etc.

Potassium feldspar melts at around 1200°C (higher than soda feldspar) producing a more a viscous melt than does sodium feldspar. It can also produce a crystalline phase (leucite) that contributes to opacity. Thus, in industry, potash feldspars are often used more for matte glazes while soda feldspar is used for glossy glazes.

Glazes high in feldspar (35% or more) are plagued by crazing problems, yet still used by tens of thousands of potters. 'Flux saturated' glazes with more than 50% feldspar may be unbalanced and lack adequate glass former or alumina to create a stable hard glass resistant to leaching.