mollocite

[tomato red glaze]

does mollocite help in crystal formation in glaze?

 

[Dick White]

I've never heard that. Molochite is just a trade name for calcined kaolin.

[Min]

I believe Molochite was used by Peter Ilsley in very small amounts (like less than 0.5%) in his macro crystalline glazes. 

[Dick White]

1 hour ago, Min said:

I believe Molochite was used by Peter Ilsley in very small amounts (like less than 0.5%) in his macro crystalline glazes. 

Yes, he used Molochite in very small amounts as a refractory alumina source to keep the very fluid macro crystalline glazes from running too much. It was not a crystal enhancement. The reason such a small amount was used is because if the fluid glaze was too stiff (in relative terms), the zinc-silicate crystals would not grow in the molten glaze. Given that Molochite is simply a UK brand name for calcined Grolleg, others of us in the crystalline rabbit hole simply use whatever kaolin is readily available, whether calcined or not. And at cone 6 macro crystalline, we don't use it at all.

[Pyewackette]

19 hours ago, Dick White said:

crystalline rabbit hole

That's an apt description.  One of the guys at the studio asked if I would be interested in getting in to crystalline glazes.  I told him that at my age I didn't think it was a good idea for me to get embroiled in an exercise in futility.

The success rate tends to be so low, it is so hard on an electric kiln's elements.  And while some of the crystalline glazes are just glorious, an awful lot of it ends up looking like there is mold growing on your pots.  I just couldn't take the high failure rate LOL!

[Min]

@tomato red glaze, did you mean Molochite? Or maybe malachite?