UNCOMMON SPECIES NOWADAYS WITH ORIGINAL PERIOSTRACUM!! Wonderful thick periostracum with excellent conditions combined with elegant dense thick vertical ribs. Thick formidable shell with natural conditions. This shell was collected fresh dead with superb conditions. F+++. Found attached under muddy stones about 5m dee. Barra de Navidad, Jalisco, Mexico. September 2026. Estimated value between 8-10 euros . Good luck and happy shelling. MEXICO PACIFIC