[Due to space limitations, we don't store raw materials at our studio but instead at our warehouse. If purchasing, please allow 2 business days for us to have your order brought from our warehouse.]
 
This calcium borosilicate glass is made by Fusion Ceramics. It is a very close substitute for Vibrantz frit 3134 formerly made by Ferro. F-12 frit initiates early melting (like Gillespie borate) promoting fuller fusion of other glaze ingredients. With the addition of enough siliceous clay, the chemistry of F-12 is very similar to frit F-19.
First fusion: 1450ºF / 788ºC.     cte: 8.18 x 10-6.