to CaO and ZnO - useful in middle temperature range. .
Can be used
as a low temperature flux if incorporated in a fritt.
often compared with CaO though interaction power is more akin
precipitate out to produce crystalline matts.
be an expensive oxide to use but can be beneficial in replacing
less desirable fluxes such as barium oxide and lead (does not
necessarily reproduce the colour responses of these oxides particularly
high barium alkaline effects).