Unusual Mexico Marks

[Buttrflygrl617]

I just acquired a few Modernist/Southwestern sterling jewelry pieces from a lady and I am having a hard time trying to determine the maker of this pair of Taxco clip ons. They are definitely made of bone & sterling and each earring back is marked differently. One has a name that I don't recognize & Mexico and the other has TB-28 (I think) & 925. Does anyone happen to recognize this maker and signature?
Thanks and have a wonderful day!
Jamie