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Fusion Frit F-12

Alternate Names: F12 Fusion,Frit F12

Description: Artware Flux Calcium Frit

Oxide Analysis Formula
CaO 20.00% 0.68
Na2O 10.40% 0.32
B2O3 23.80% 0.65
Al2O3 0.80% 0.01
SiO2 45.00% 1.43
Oxide Weight 190.75
Formula Weight 190.75

Related Information

Fusion F-12 vs Ferro Frit 3134 at cone 04

Melt flow test of Frit 3134 vs F-12

On paper, Fusion F-12 has a very similar chemistry to 3134. And in practice it also appears very similar, although a little more melt-fluid than the 3134.

Ravenscrag GR6-A glaze with Frit 3134 and Fusion F-12

As this cone 6 melt flow test demonstrates, the Fusion F-12 is giving very similar performance to the Ferro. The GR6-A recipe is just 80% Ravenscrag Slip and 20% frit (10% zircopax has also been added to opacify). The degree-of-melt on the glazed tiles in also very similar, however notice that some of the whiteness has been lost on the second F-12 tile (the first is frit 3134). We are attributing this to the better melting of F-12, that is amplifying the color of iron present in the Ravenscrag Slip. For the third tile we reduced the frit to 15%, that has whitened it somewhat. Likely an increase in the zircon and would whiten it more.

G2926B using Fusion Frit F-12 instead of Ferro 3134

Melt fluidity tester comparing two versions of G2926B

G2926B is a popular recipe that saw alarm during 2021 because of the difficulty in getting Ferro frit 3134. This motivated us to get a supply of the Fusion equivalent, F-12. This is a demonstration of how effective a melt fluidity test can be in comparing two glazes. Not only does the test compare the degree of melt but also surface reaction to LOI (defects), iron content and melt surface tension.


Materials Ferro Frit 3134
A frit with 23% B2O3. The most common of frits used in pottery in North America. Around the world, other companies make frits of equivalent chemistry.
Materials Pemco Frit P-54
Materials General Frit GF-111
Materials Frit
Frits are made by melting mixes of raw materials, quenching the melt in water, grinding the pebbles into a powder. Frits have chemistries raw materials cannot.
Materials Hommel Frit 14
Materials Solargil Frit FR8
Typecodes Frit
A frit is the powdered form a man-made glass. Frits are premelted, then ground to a glass. They have tightly controlled chemistries, they are available for glazes of all types.


Co-efficient of Linear Expansion 8.18
Frit Softening Point 1450F
By Tony Hansen
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