10mm. High quality faux pearls made in Japan for "Marvella". Marvella made high quality costume jewelry and is no longer in business. These rare old pearls are a wonderful baroque shape and nice size to work with. The color is a rich dark silver to imitate rare black pearls of the South Seas. We have the matching clasp available as well - Item #16864 in the Rhinestone and other Old Clasps Section of the site.