BLACK OPAL AND DIAMOND RING, CIRCA 1920. The oval-shaped black opal measuring approximately 20.5 by 11.2 by 4.9 mm., the sides accented with buckle motifs set with single-cut and baguette diamonds, mounted in platinum, size 7¾.
http://diamondsinthelibrary.com/award-winning-omi-prive-black-opal-ring/ The award-winning Lighting Ridge black opal ring by Omi Privé, with diamonds, sapphires, and tsavorite garnet; top and side view
UNIQUELY CHRYSOCOLLA RING -- Chrysocolla druzy's defining characteristic is that no two are exactly alike. Ananda Khalsa frames each in matte 22kt gold, a diamond trio above and below. Handmade in USA of sterling silver. $1,200.00