onglaze powders

[Namron]

I have been given a substantial quantity of "onglaze" ceramic powders. I have successfully made my own underglazes for sometime and I have a simple question.

Can I use Onglaze ceramic powder to make my own underglazes with addition of my standard medium.

thanks

[Callie Beller Diesel]

Hi and welcome to the forum!

What’s the brand name on labels? We might have to do some googling to find specs to answer this properly.

Overglaze powders aren’t sold as such in North America, although I have come across the occasional recipe for an overglaze. We also usually only get either Mason stains, or underglazes that are premixed. We don’t have ones that we have to add medium to. If you could let us know which brand of medium you’re using, that’d be appreciated too.

[Kelly in AK]

Any more information you can provide about these powders will help you get an accurate answer. The term “onglaze” makes me imagine they’re for China painting, and would be formulated for firing around cone 018. Fired higher, some colors would stay the same while others may change a lot. But that may not be what you have at all, so it’s hard to say. 

[Namron]

I have found out that the  donor used them for painting pre-glazed tableware. There are approx 600 small containers of the powders from a variety of suppliers. I have checked online for further information from the suppliers and found that they are meant for firing around 800°C .

Since kiln time is limited for experimentally firings I have decided to donate them to a china painting group who are collecting them today.

Thanks for your help and input.

[Kelly in AK]

China painters, with their mediums and tiny vials will rejoice!