This is an example of how useful a flow tester can be to check new glaze recipes before putting them on ware and into your kiln. This was fired to only cone 4, yet that fritted glaze on the left is completely over-melted. The other one is not doing anything at all. These balls are easy to make, you only need weigh out a 50 gram batch of glaze, screen it, then pour it on a plaster bat until it is dewatered enough to be plastic enough to roll these 10 gram balls.
A Low Cost Tester of Glaze Melt Fluidity
This device to measure glaze melt fluidity helps you better understand your glazes and materials and solve all sorts of problems.
Reducing the Firing Temperature of a Glaze From Cone 10 to 6
Moving a cone 10 high temperature glaze down to cone 5-6 can require major surgery on the recipe or the transplantation of the color and surface mechanisms into a similar cone 6 base glaze.
Ceramic glazes melt and flow according to their chemistry and mineralogy. Observing and measuring the nature and amount of flow is important in understanding them.
Every glossy ceramic glaze is actually a base transparent with added opacifiers and colorants. So understand how to make a good transparent, then build other glazes on it.