FFP 45 Feldspar
A standard material in Glazecalc's library: its oxide analysis, unity contribution and hazards.
What it is
- Kind
- Feldspars and stones
- Formula
- SiO₂ 78%, Al₂O₃ 13%, Na₂O 4.1%, K₂O 4%, CaO 0.5%, Fe₂O₃ 0.07%
- Also called
- Feldspar FFP45, FFP 45 pegmatite, Potclays 3430
- Made by
- Sibelco (Finland)
- Sold in
- UK
- Source
- Sibelco ceramics product selector, feldspars for glazes and engobes (FFP 45 pegmatite, origin Finland) (2021-06)
Finnish feldspar-quartz pegmatite that Potclays sells as an alternative to the now-unavailable Forshammar feldspar. Its high silica makes it behave more like Cornish stone than a true feldspar.
Oxide analysis and unity formula
Glazecalc has the analysis of FFP 45 Feldspar as weight percent of the raw material. The unity contribution is the moles of each oxide in the amount of FFP 45 Feldspar that holds 1.0 mole of flux, which is how Glazecalc adds it into a recipe's unity formula.
| Oxide | Weight % | Unity contribution |
|---|---|---|
| SiO₂ | 78 | 11.045 |
| Al₂O₃ | 13 | 1.085 |
| Na₂O | 4.1 | 0.563 |
| K₂O | 4 | 0.361 |
| CaO | 0.5 | 0.076 |
| Fe₂O₃ | 0.07 | 0.004 |
- Equivalent weight
- 850.83
- Fired weight
- 850.83
- Loss on ignition
- 0%
The equivalent weight is the grams of FFP 45 Feldspar that hold 1.0 mole of flux. The fired weight is what is left of that after firing.
Hazards and safety
Hazards: Fine dust contains respirable crystalline silica; avoid breathing it.
Use it in a recipe
Add FFP 45 Feldspar to a recipe in the Glazecalc calculator to see what it does to a glaze's unity formula.