Hallmark on Watch Cuff

I am having trouble finding the person this ALBERTO hallmark belongs to. I have exhausted my resources and I am hoping the forum can assist.


The only name I am coming across is Alberto Contreras, could that be a C around Alberto? He is a famous artist, couldn’t find anything like this or the hallmark, but I think maybe a little exploring. Maybe he had his own shop and piece makers?

Thanks for the pointer! I will check it out and see what I can find out.