Mystery Zuni Mark - "R.G.C." Engraved by Hand

[ThePawnbroker]

Hi all, and thank you for allowing me to step into this community, that I've watched from the outside, for years and years.

I've got several Native American pieces that have me stumped, and would appreciate any information anyone has on the markings. This one is a Zuni dancer bolo tie set with turquoise, mother of pearl, yellow mother of pearl, spiny oyster shell, and jet. The reverse has a hand-engraved signature that reads "R.G.C." inside what appears to be two stylized ampersands. Another Zuni inlay piece that also has me stumped, has these same stylings before and after an "E.G." mark. Perhaps these stylized ampersands might represent a certain pueblo?





Thanks again. Looking forward to posting more of the pieces I can't figure out.

Sincerely,
Scott

[ThePawnbroker]

Here is the piece I referenced with a similar signature. This one reads "E.G." between two stylized ampersands.

The bolo depicts a horse, and has inlay work set with turquoise, jet, mother of pearl, yellow mother of pearl, and spiny oyster shell. Any additional information on this signature would be greatly appreciated.