Item #: CH-CORNSUB
Priced per pound.
This is a a cornwall substitute blend. We suggest testing before committing to large quantities.
Cornwall Stone is a low-iron feldspar blend used in ceramics as a source of fluxing oxides in both clay bodies and glazes. It is used in clay bodies to give strength while firing and in engobes because of its adhesive properties. With the addition of a suitable flux, Cornwall Stone can also be used as a glaze.
Cornwall Stone is an alkaline flux containing calcium and potassium, and its chemical formula is K2O/Na2O/CaO×Al2O3×10SiO2-HT. Because it was mined from granite rock (traditionally, from the Cornwall area, UK), it is actually composed of a combination of minerals, and the ratio of these chemicals could vary somewhat drastically. This means that potters who used this material over long periods may notice different results when using the same recipes. As a glaze component, Cornwall Stone is similar to feldspar, -- indeed, it is composed of different feldspathic materials -- though it is different enough that it cannot be replaced by a feldspar alone.
The original Cornwall Stone Mine has been closed, and now the material is produced synthetically. Hamill and Gillespie now have this product manufactured for them and is the closest to the original -- plus, now that Cornwall Stone is produced in a lab environment, the variations that existed with the original material are no loner a problem for potters. Cornwall Stone is sometimes referred to as English Cornish
A full bag is 55 lbs.
WARNING: This product can expose you to chemicals including Silica, crystalline (airborne particles of respirable size), which are known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.
Learn More about the NEW HG Cornwall Stone.