Boraq
A standard material in Glazecalc's library: its oxide analysis, unity contribution and hazards.
What it is
- Kind
- Boron sources
- Status
- Discontinued
- Formula
- CaO 21.8%, K₂O 0.6%, MgO 2.3%, Na₂O 3.6%, B₂O₃ 30%, Al₂O₃ 2.8%, SiO₂ 13.5%, Fe₂O₃ 0.2%, LOI 25.3%
- Also called
- Boraq 1, Plainsman L3127E
- Made by
- Plainsman Clays Ltd. (Medicine Hat, Alberta, Canada)
- Sold in
- US
- Similar materials
- Gillespie Borate
- Replaces
- Gerstley Borate
- Source
- Digitalfire Reference Library: Boraq
Legacy plastic Gerstley Borate substitute developed by Plainsman Clays in 2000 and sold in the early 2000s; no longer made. Keep only for old recipes; Gillespie Borate is the current replacement.
Plainsman's materials page listed it until late 2017 and no longer did in January 2018.
Oxide analysis and unity formula
Glazecalc has the analysis of Boraq as weight percent of the raw material. The unity contribution is the moles of each oxide in the amount of Boraq that holds 1.0 mole of flux, which is how Glazecalc adds it into a recipe's unity formula.
| Oxide | Weight % | Unity contribution |
|---|---|---|
| CaO | 21.8 | 0.762 |
| K₂O | 0.6 | 0.012 |
| MgO | 2.3 | 0.112 |
| Na₂O | 3.6 | 0.114 |
| B₂O₃ | 30 | 0.845 |
| Al₂O₃ | 2.8 | 0.054 |
| SiO₂ | 13.5 | 0.440 |
| Fe₂O₃ | 0.2 | 0.002 |
- Equivalent weight
- 195.97
- Fired weight
- 146.39
- Loss on ignition
- 25.3%
The equivalent weight is the grams of Boraq that hold 1.0 mole of flux. The fired weight is what is left of that after firing.
Hazards and safety
Hazards: Borate: do not ingest; high-dose animal studies of inorganic borates show reproductive/developmental effects (U.S. Borax Gerstley Borate MSDS, Apr 2013). Avoid breathing dust.
Use it in a recipe
Add Boraq to a recipe in the Glazecalc calculator to see what it does to a glaze's unity formula.