The sterling cone beads look like they were commercially made.
What is this? An 18K repair on the bezel? [ATTACH]
Take better photos ,too much light and reflections maybe try a light gray background. Appears the ring has been damaged and "repairs"made to it.
Rolled gold,silver layer between two gold layers instead of base metal.
The stone looks like rhodonite,construction could be artisan/hobbyist. No reason for it to have a silver mark since it is illegal to mark precious...
https://www.realorrepro.com/article/Cinnabar
If Tiffany quality control had inspected them they would have gone into the scrap bucket,poor solder joint.
Try a soft toothbrush and a baking soda paste made with a little water to make the paste.
The ring could have been made hobbyist,etc. the cores have been available with a number of materials for some years....
It could have been made by different tribal members or Latino,Caucasian.Legally if it doesn't have a NA maker's mark it is SW and not NA.
The link komokwa posted,the ring was commercially made and not considered NA made.
Did you read the info in the link,the ring was not native American.
Get a good in focus closeup of the stones,they may be variscite.
Tobacco pipe/cigarette holder with the same maker's mark........
Are the stones glued in? A sphere may fit.... https://www.google.com/search?client=firefox-b-1-d&q=8mm+gemstone+spheres
Have you viewed this list? https://www.925-1000.com/a_Standards.html
Sweetheart pin... https://www.ebay.com/itm/125417196654
The copper was acid etched.
The mark is just right of the G in sterling.
Looks like the mark was cut and partially covered with solder while sizing the ring.
Separate names with a comma.
