[huhnra]

What is meant by "fusing" a salt, in my case zinc chloride? I am curious of the method, as ZnCl2 is very hygroscopic. I have melted samples of (fairly old) zinc chloride, whereupon the white solid browned and then turned black. The same happened under inert atmosphere - any idea what's happening? Thanks, RH

[Demotivator]

Fusing means melting, sometimes in order to remove water tied to the salt. Sometimes fusing means melting a salt with a refractory compound in order to dissolve/decompose the refractory into the salt medium.
Well, ZnO is white, but if Zn picks up some other metal contaminants from the crucible, it could turn dark.