New vintage hematite STER silver cocktail ring

New vintage hematite STER silver cocktail ring Minimalist design. Very SLEEK. Curves and long elongated oval shape of hematite cabochon. Plus the shine from polished silver and hematite! Heavy weight (one of my heaviest rings). Very solid. Thick band. Size 6 Hematite oval: 9x23 mm Band around hematite: 2-3 mm wide x 1 mm thick Band: 2 mm wide, 1-3 mm thick May Be a man’s ring originally but unisex by today’s standards! New vintage c. 1970s-1980s. Probably made in Mexico. Hallmarks: see pictures 1. Band: STER 2. Band: RUB (?) 3. Under setting: SILV or STS Was black and I cleaned it up with toothpaste!