Heated Selenite bead wire consists of beads made of selenite, a variety of gypsum known for its satin sheen and softness. The “Rainbow” particularity refers to a special heat treatment that gives the surface of the pearls an iridescent effect, creating multi-colored reflections that vary according to the light. These pearls may be slightly translucent with a natural milky hue that enhances their brilliance. Natural stone bead wire Pearl diameter: 4/6/8/10/12 mm Hole size: 0.8-1mm Number of beads per 38 cm thread: 4 mm = about 90 beads 6mm = about 63 beads 8mm = about 48 beads 10mm = about 38 beads 12mm = about 32 beads