Here's the reply from Jennifer at PP.
"[FONT='Arial','sans-serif']The width of the actual chain is .8mm, but the end with the screw is a bit larger ? about 1.1mm so the pearls had to be drilled to fit over the screw end of the necklace..."[/FONT]
[FONT='Arial','sans-serif'][/FONT]
[FONT='Arial','sans-serif'][/FONT]