G-200HP FELDSPAR POTASH : 50 Pound Bag

A significant change has been made in the G-200 Feldspar. If you are using this product you will need to make some adjustments to your clay & glaze formulas. The new G-200HP will be higher in potassium and alkali levels. The reason for the change is a decision by Imerys Ceramics to stop blending feldspar from two different deposits. For some time now the Feldspar Corporation has been blending their Sodium Feldspar from Spruce pine, NC with their Potassium Feldspar from Monticello, GA. This was done in effort to keep the same published levels of sodium and potassium as they had in a mine that is now depleted.

Imerys Ceramics is recommending to their customers to blend 28-30 % of sodium feldspar to the new G-200HP feldspar. (7 Parts to 3 Parts) If you are buying prepared clays or glazes from Sheffield Pottery this will be done for you. If you are mixing your own, you will need to blend the G-200HP with Minspar 200 or Kona F4 Feldspar. Both are mined in Spruce pine, NC and have almost identical chemical properties. We are currently using the Kona F4 but will be switching to Minspar 200 as the Kona F4 mine is closing.

You may still be able to use the new G-200HP without blending in some formulas but you should definitely do proper testing first.