Need help identifying hallmark "SM"

Would love to know the artist who created these earrings. Came from my grandmother who lived in Arizona and purchased turquoise jewelry from the 1950’s up until a few years ago.
Hallmark “SM” on both earrings. Thanks!

I did a pretty good search and came up empty handed. Could possible be a WS. This is a popular style and we get ours from a Claudia Haloo.

Wow @Jason ! I think you might be right about it possibly being WS. I was certain it was an “M” because of the straight sides, but like you, my searches turned up nothing. I searched for WS and found the Willie Shaw has signed his pieces both with a more typical W stamp, AND an M stamp as pictured below. And it appears that he does inlays work. Wish I could know for sure, but I am satisfied with a possibility.
Thank you!
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