Agate Necklace and Bracelet Set (Pure Black, 3Pcs). A stunning set to serve your desire for pure black with 1 necklace and 2 bracelets. Agate Necklace (Black). Size: necklace length 17"; bead 10mm (0.39 inch diameter). 1 Agate Bracelet (Black) with large beads. Size: bead 0.44 inch diameter). 1 Agate Bracelet (Black_S) with smaller beads. Size: bead 8mm (0.31 inch diameter). Stretching. Material: Agate. Color: pure black.