New vintage silver abalone shell ring

New vintage silver abalone shell ring Rustic x industrial x minimalist. Oval abalone shell cabochon: c. 4x8 mm Bezel setting: 1 mm deep Brown mark in center. Pearlescent shimmery sheen. Pale pale pink, white-grey, and a touch of green or blue in the shimmer. Silver wire circles on either side welded to the frame. Siver wire frame band. The band is squished together to form a y near the top and only welded at the back. (Almost 1 mm thick wires) +1 mm to 2 mm to 4 mm at widest. Nice parallel lines and simple shapes. Size 6 (slightly smaller but bigger than size 5.5) New vintage c. 1970s. Probably handmade in Mexico. Genuine abalone shell and silver. Hallmarks in pictures but I can’t make them out except for a “2” like in some Mexican hallmarks.