Possibly Vintage, 13x15mm Turquoise cabochon in solid sterling silver ring!

I found this at an estate and I thought it was potentially native. The letters M.E. are carved into the back of the ring, but of course I can't be sure who the artisan is. Either way, this is a solid sterling silver (not marked, but acid tested), ring with a stunning 13x15mm (ish) turquoise cabochon at the forefront. Size 8. Please inspect and enlarge the pictures to assess the condition of the item for yourself. Please ask any questions you might have. New/Vintage/Pre-owned/antique items are being sold as is. Pictures are not altered and colors have not been adjusted. Due to technical reasons, colors may appear differently on your electronic devices. Pictures may also be enlarged to show better detail. 💎gemstone, 14k, 10k, 18k, sterling, silver, gold, estate, ring, pendant, earrings, loose, natural, stone, genuine, synthetic, lab, diamond, moissanite, vintage, real, gemstone jewelry, engagement, anniversary, promise, wedding, plated, gem, necklace, brooch, fire, crystal, jewel, gift, authentic, collectable, affordable, tested, luxury, natural, opal, emerald, aquamarine, topaz, sapphire, tourmaline, zircon, spinel, investment, ruby, alexandrite, stamped, gift, birthstone, mom, mother, fiance, wife, girlfriend, designer, southwestern, western, native, boho💎