These center-drilled Czech glass beads are called Saturns and they feature a knobby notched ring showing the core glass. This listing is for 1 strand of 25 beads.
These beads were manufactured in the Czech Republic and are made of glass. They are 6mm tall by 4mm in diameter, however, as is the nature of Czech beads, some may be a little bigger or a little smaller. These beads have a .9mm center-drilled hole, but again some holes are a little smaller or a little bigger.
All photos have been taken outdoors using sunlight, but as always, computer and mobile screens display colors a little differently.