Height 2 in., Width 2 in. This group of three large sterling silver beads is each modeled in the form of a natural gastropod shell rendered in repousse -- the technique of hammering and shaping silver from the reverse to create three dimensional relief -- comprising two flattened disc-form moon snail or sundial shell beads with spiraling concentric line decoration oxidized to emphasize the grooves, and one tall conical turritella or auger shell bead with stepped spiral banding tapering to a small point, each piece drilled through at the apex for stringing on cord or wire. Large hollow repousse silver shell beads of this quality and scale are characteristic of two distinct silversmithing traditions -- the celebrated Taxco Mexico silver workshops established in the 1930s under the influence of American designer William Spratling, whose revival of pre-Hispanic forms and techniques produced some of the most collectable 20th century artisan silver jewelry in the Americas, and the Southwestern American Native and studio silver traditions of the same period. The naturalistic precision of the shell forms -- each faithfully reproducing the actual geometry of the marine gastropod with its mathematically precise Fibonacci spiral -- reflects the close observation of natural forms that characterizes the finest artisan silver work in both traditions. The pieces show honest age tarnish and surface wear consistent with vintage production. Condition is good with the repousse forms intact and the drill holes sound.