Gubelin Red Spinel Diamond Ring at 1stDibs Untreated Red Spinel Ring, 4.07 Carat For Sale at 1stDibs what is a Victorian Pink Spinel and Rose Cut Diamond Dress Ring ??? The Vintage Red Spinel and Diamonds Ring, 18k White Gold Red Spinel and Diamonds. An impressive solitaire ring set with a rectangular cut red spinel stone. Measures 8x6mm. Head measures 8x6mm, depth 7. 5mm. Weight 5. 3grams. A very good heavy weight band and setting. Stamped 585, tests as 14 carat gold, overseas manufacture so no hallmarks. Size P, we can resize free of charge.