FRITTE 3134 5 KG
laag in aluminium / hoog calcium boor silicaat
19.5 % CaO
10.1 % Na2O
2.0 % Al2O3
22.8 % B2O3
45.5 % SiO2
It has almost no alumina. That means, as already stated, that Al2O3 can be supplied by clay, giving the glaze better suspension and hardening properties. Conversely, adding Frit 3134 to a recipe (to supply boron for example) does not require reduction of clay content.
It has high sodium. That means that it's presence enables reducing feldspar content which in turn provides even more opportunity to source Al2O3 from kaolin or clay.
It has high boron. That gives it a lot of bang-for-buck as a flux, especially in middle temperature.
It has a very high CaO content. That makes it useful for developing chrome-tin pinks and maroons.