The material of the stone is unknown. *Although cleaned, please refrain from purchasing if you are concerned about scratches or the characteristic blackening of silver, as this is a used item. This is one of my favorites, but I'm selling it to declutter as I have too many accessories. I may change my mind and remove the listing, so if you are considering a purchase, please do so quickly... (＞_＜) ★☆★☆★☆★☆★☆★☆★☆★ silver925 Sterling Silver Sparkling Ring Black Zirconia Stone