.15 Diamond Cluster Stacking Ring in 18k Yellow Gold. 15 Diamond Cluster Stacking Ring in 18k Yellow Gold. This modern cluster ring features . 15 carats of diamonds finished in polished 18 karat yellow gold. At the center of the ring, two (2) . 02 carat baguette diamonds are channel set side by side. The diamonds are near colorless and highly brilliant. The center stones are flanked by six (6) . 0183 accent diamonds. The accent diamonds are prong set in triangle formation at the shoulders of the band.