Generally speaking, the pore size of jasper beads depends on their uses and processing methods. Jasper beads are usually used to make bracelets, necklaces, pendants and other jewelry, so the size of the hole needs to be suitable for beads or chains to pass through.

Usually, the aperture of jasper beads is between 1.0mm and 2.5 mm. The smaller aperture is suitable for wearing thin bead chains or fine iron wires, and the larger aperture is suitable for wearing thick bead chains or thick iron wires. This ensures that the beads can move freely and will not be too tight or easily broken.

It should be noted that jasper is a kind of gem material with high hardness, and it needs to use appropriate tools and techniques to drill holes during processing. The size of the hole also needs to be determined according to the size and shape of the beads to ensure the stability and aesthetics of the beads.

In addition, the hole size of jasper beads can be adjusted according to personal preferences and design requirements. Some people like a smaller hole diameter to better show the color and luster of beads, while others like a larger hole diameter to match a thicker chain or rope.

In a word, the aperture of jasper beads is generally between 1.0mm-2.5mm, depending on the use, processing method and personal preference.