This melt flow tester demonstrates the beautiful crystal-clear glass this zinc frit creates by 1700F. It fits this porcelain without crazing, even though it is very thick and high in sodium (the high zinc and boron are countering it to keep the thermal expansion down). It runs off the end of the runway around 1600F on this GLFL test, rivalling lead bisilicate. This is a more concentrated boron source than even Gerstley Borate. Everything about this material screams “ultra gloss”. What a material to build a fluid-melt reactive super-glaze on!

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These 10g balls GBMF test balls were fired far lower than typical bisque; notice how many of them are already melting well! Frit 3602 is lead bisilicate. Maybe you always thought lead was the best melter. But it got "smoked" by the Fusion FZ-16 high-zinc, high-boron, zero-alumina frit! However, notice the FZ-16 is crazing badly; that is a problem for many applications using this high KNaO frit. Want to get some of this frit for pottery? You can't; Fusion Ceramics doesn't want to handle retail sales of smaller quantities.
Notice that, at this low temperature, each frit has a distinctive melt fingerprint that makes it recognizable.
Notice that the common North American pottery frits on the bottom row: 3195, 3249, 3124, 3110 (and 3134 in the second row) fire distinctly differently. Notice Fusion F69. It looks like 3249 because it is a substitute for it! F-75 is a substitute for 3110 (sharing the same melting pattern but having different micro-bubble clouding).
| Materials |
Fusion Frit FZ-16
The champion in our frit melt-off competitition. This frit showcases the amazing fluxing power of boron and zinc working together. It is 15.5% ZnO. |
| Projects | Comparing the Melt Fluidity of 16 Frits |
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