Size: 4mm (84 - 95 beads)
         6mm (63 - 58 beads)
         8mm (47 - 543 beads)
         10mm (38 - 36 beads)
         12mm (30 - 31 beads)

Beads hole size:
4mm round beads hole size - approx 0.6mm
6mm round beads hole size - approx 0.8mm - 1mm
8mm round beads hole size - approx 1mm
10mm round beads hole size - approx 1mm - 1.2mm
12mm round beads hole size - approx 1mm - 1.5mm

Beads sizes do vary between different gemstones or even batches for the same gemstone. 
Beads colors do vary between different gemstones or even batches for the same gemstone. 
Please note that there could be a variation of up to 1mm - 1.5mm in size.