Ark Angel Alchemy 90ct. Sterling Silver Natural Rainbow Moonstone 18" Necklace w/Extender Box Rainbow Moonstone necklace is over 228 carats total weight, 45 grams.* 18" Sterling Silver Cable Chain with hook and link clasp. The gemstones span 137mm and the necklace is 32mm in width at the center.* The oval stones measure 8mm x 10mm.* Includes a Free, Silver Gift Box Handmade, Polished Finish, Excellent Quality, Meticulous Detail.