6.2 to 6.5 millimeters I will be listing items gradually to organize my collection. * To prevent any issues, please ask any questions you may have regarding the size of the beads, inner diameter, etc., before purchasing. Please be aware that you will not be able to confirm these details through images after purchase. * There may be minor chips, cracks, and scratches. Thank you for your understanding. #NaturalStone #NaturalStoneBracelet #Scolecite