Monthly Tech-Tip from Tony Hansen SignUp

No tracking! No ads!

1-9 | A | B | C | D | E | F | Frits | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Disodium Octaborate Tetrahydrate

Alternate Names: Na2B8O13.4H2O, Polybor

Oxide Analysis Formula
Na2O 15.02% 1.00
B2O3 67.50% 4.00
H2O 17.48%n/a
Oxide Weight 340.63
Formula Weight 412.78


CAS Number 12280-03-4

This is a mild alkaline salt consisting of a fine white powder that is readily soluble in water. It dissolves even in cool water to give supersaturated solutions with high boron concentrations. This material is not generally used in ceramics.

It shows little tendency to cake except after prolonged storage or if it becomes severely wetted by rain or substantial water penetration. It is also capable of absorbing moisture if exposed to a humid environment.

Related Information


Polybor Data Sheet
Materials Boric Acid
Materials Anhydrous Borax
A white, odorless product crystalline granular by dehydrating Borax to remove the crystal bound water.
Materials Borax Decahydrate
Typecodes Flux Source
Materials that source Na2O, K2O, Li2O, CaO, MgO and other fluxes but are not feldspars or frits. Remember that materials can be flux sources but also perform many other roles. For example, talc is a flux in high temperature glazes, but a matting agent in low temperatures ones. It can also be a flux, a filler and an expansion increaser in bodies.
Minerals Borate Minerals
The major borate minerals are Colemanite and Ulexite. The geology required for borates is found in v
By Tony Hansen
Follow me on

Got a Question?

Buy me a coffee and we can talk, All Rights Reserved
Privacy Policy