1x Preciosa Jet Black Crystal Drops 10mm. Beautiful quality Czech crystal glass from Preciosa. Dainty 10mm drops (height from tip to tip) with a 6mm diameter around the plumpest part. Hole lies horizontally approximately 1.5mm from the top tip, and is 2mm wide, 1mm in diameter. Czech glass colour code 23980. To find other jet black Czech glass beads with the same colour code, please enter it into the Search box.