Alumina is a compound that significantly improves the hardness, heat resistance and durability of clay bodys and glazes. Its presence in ceramic glazes acts as a stabilizer, reducing the risk of run-off, bubble formation and surface defects during firing. This contributes to a uniform and resistant surface, especially important in pieces subjected to intensive use, such as tableware and cookware.
In addition, alumina increases the abrasion resistance of the glazes, protecting the piece from scratches and wear over time. In high-temperature glazes, it can also help regulate thermal expansion, preventing cracking or crazing in stoneware and porcelain. As a refractory oxide, alumina is used in the production of technical and refractory ceramics, where high resistance to temperature and thermal changes is required.
Interesting Fact
Alumina is one of the hardest constituents in nature, and in its crystalline form is known as corundum, the second hardest mineral after diamond. This makes it a key material for industrial and technical ceramics.
Helpful Tip
Use alumina to improve the durability of your glazes, but avoid adding too much, as it can cause the glaze to lose its shine.
