What is Gerstley borate used for?
Gerstley Borate is a sodium-calcium-borate compound used in ceramics as a low and mid-range temperature flux. It is essentially a source of boron in glazes, and acts as a melting agent. It also can act somewhat as an opacifier and prevent crazing.
Is Gerstley borate a clay?
Thus it is common to find Gerstley-Borate-based recipes having no clay content. GB natural source of boron that was mined in southern California for many years. Mineralogically it is a combination of colemanite, ulexite and high plasticity clay (likely hectorite).
What can you use instead of Gerstley borate?
Gillespie Borate™
Description : Gillespie Borate™ is a blended borate mineral for use in glaze formulas replacing Gerstley Borate on a pound for pound basis.
What does calcium borate do?
Calcium Borate is an insoluble form of boron a natural frit. Used as a flux in all types of glaze, it also reduces crazing tendencies. It develops opalescence typical of boron compounds and in large quantities a broken mottled surface. A suitable raku glaze.
Is Gerstley borate borax?
Gerstley borate is named after James Gerstley, former managing director of Borax Consolidated Ltd. It is manufactured by U.S. Borax and Chemical Corp.; the mine is located near Death Valley, CA. G.B. is an inexpensive source of B2O3 and CaO in glazes. It is often used in place of colemanite.
Is Gerstley borate the same as Gillespie borate?
Mineral Match — Gillespie Borate™ provides the same minerals to the glaze as Gerstley Borate, thus imparting the same glaze activity, texture and effects.
Where is Gerstley borate mined?
It is manufactured by U.S. Borax and Chemical Corp.; the mine is located near Death Valley, CA. G.B. is an inexpensive source of B2O3 and CaO in glazes.
Is Gillespie borate the same as Gerstley borate?
Gillespie Borate™ is a blended borate mineral for use in glaze formulas replacing Gerstley Borate on a pound-for-pound basis. Mineral Match — Gillespie Borate™ provides the same minerals to the glaze as Gerstley Borate, thus imparting the same glaze activity, texture and effects.
Is borate a metal?
A number of metal borates are known. They are produced by treating boric acid or boron oxides with metal oxides.
