Welding Tips and Tricks

I have been working recently with tig tacking perforated sheet metal. About 1/16 thickness to solid plate sheet metal, a little thinner. We are using a silicon bronze 1/16 wire for tacking. I think the perforated material is galvanized, they say it is aluminized. When tacking there is a whiteish smoke rising off, and when the tack is completed there is a whiteish flakey residue closest to the tack and a black sooty residue outside of the white area. Is there an easy quick way to for sure tell whether the material is galvanized, sure seems like it to me. Thanks for any help or input.

That’s like asking if it’s a red apple or a green apple. The difference will be hard to tell. The affect to the weld will be about the same either way. Lots of exhaust pipe is aluminized. It gets welded. The whiteish residue will show up with either coating. When welding.