Early cast tag inquiry

[Ben Guegain]

I have a question regarding early cast tags on fans/motors (specifically for a Tesla).

Did the early cast tags have the black oxidation on the low spots of the tag so that the brass popped as many later stamped tags did? Or was it all just pure brass? I have seen it both ways on old metal machinery like metal lathes and mills. Sometimes those early tags had even colored backgrounds. I’m inclined to think it was not colored and at all but wanted to be sure.

Thanks!