DUE TO CHANGES IN COURIER WEIGHT REGULATIONS, WE CAN NO LONGER SHIP 25KG BAGS IN A BOX AS IT IS OVER THE 25KG MAXIMUM SHIPMENT. THEY WILL NEED TO BE SHIPPED IN HEAVY DUTY PLASTIC BAGS. IF 6 OR MORE BAGS ARE ORDERED, WE CAN SHIP VIA A PALLET. UNFORTUANETLY, WE WONT BE ABLE TO ASSIST IN ANY CLAIMS IF THERE IS DAMAGE IN TRANSIT, AS THIS IS OUT OF OUR CONTROL.
Feldspar Sodium YS200 is also known as Na-Feldspar, Na Feldspar, Albite, Soda Feldspar
Soda Feldspar is generally a clean white mineral that sources sodium, alumina and silica along with some potassium and calcium. No actual materials have the ideal formula shown here, they all have some K2O and small amounts of other contaminants. Manufacturers refer to their materials as 'soda' if Na2O predominates over K2O (often manufacturers refer to their materials at soda-potash feldspars (or vice versa) if neither of the oxides predominates). Nepheline Syenite is often used in similar circumstances, however it has a higher alumina content (often the lower alumina content of soda feldspar provides more room in glaze recipes for alumina sourcing ball clay or kaolin to help suspend the slurry).
In many cases soda and potash feldspar are interchangeable in glaze recipes. However, some differences will be apparent. Soda feldspar normally melts better. Also, slightly different colour responses will be encountered (i.e. cobalt tends toward purple copper toward blue with soda spar). Sometimes colours will be brighter with soda feldspar. In addition, soda spar has a higher coefficient of expansion and melts earlier and has a shorter range before it begins to volatilize.
Crazing Alert:
Because sodium has the highest expansion of all oxides and because it is high in this material, glazes with a lot of soda spar will almost always craze. Thus, if any glaze recipe has more than 30% soda feldspar, it is wise to test carefully to assure the glaze is not in tension (use glaze calculation software to reduce the Na2O and replace it with CaO, MgO or another fluxing oxide if possible). It is important to remember that if a glaze is high in Na2O, diluting it with other oxides to try to reduce crazing is a losing battle, it is the cause of the problem, it needs to be reduced.
