This is a 16.5mm bead.
I have sold on eBay in the past for many many years my lamp work feeds were quite popular back in the day. I am hoping to get back on eBay regularly, but at this point I sell elsewhere until I can gain back a base here. I miss it very much.
I make handmade borosilicate as well as Moretti glass beads. Now for 25 years.
This bead is cored with sterling silver. Hole is 4.75mm fits pandora chains.