10-13.5mm Long Cultured Baroque Pearl, Mixed Gem Necklace, Silver Clasp Our 10-13.5mm cultured freshwater pearl and mixed gem necklace is designed in generous long lengths to show off the one-of-a-kind shape of each pearl, then enlivened with fluorite in bright hues and lime-colored crystal. Sterling silver clasp. Pearl birthstones are the perfect gift for June birthdays.