Adonia: Heart-cut Simulated Aquamarine and IOF CZ Promise Friendship Ring 925 Silver, 3144 Made with a Simulated Aquamarine Solitaire. A beautiful and elegant choice as a promise, friendship or commitment ring! Measures only about 7mm in depth, so it's a great choice for even smaller hands or fingers. Made with Solid 925 Sterling Silver with protective White Rhodium finish.