Fat, doughnut-shaped bead with a small perforation. The surface is smooth with a warm, soft luster. Diameter 16.5 mm; thickness, 13.0 mm; diameter of perforation, 1.5-2. mm. Translucent, sky-blue chalcedony with opaque white streaks. Cut, bored (from both sides) and polished. Blue chalcedony for seals is common during the late Babylonian and Achaemenid periods, but conspicuously missing from Sassanian contexts. Known sources are in Turkey and the islands.