Please help identify

[terris126]

Hi. I can make out 925 and Mexico on these sterling tuquoise heart earrings, but need help with what is stamped in the middle.
Thanks!

[Traintime]

Too blurred to read clearly, but you might look at the TC-45 sample here for comparison to late-era maker registration system?: https://www.925-1000.com/mexican_marks.html