Gold Tanzanite & Diamond Cluster Ring Rings from Cavendish Jewellers Vintage Tanzanite & Diamond Cluster Ring Rings from Cavendish Lot 19 A tanzanite and diamond square cluster ring. Tiffany and Co. Tanzanite Diamond Platinum Cluster Ring at 1stDibs Vivid Tanzanite and Diamond Cluster Ring Rings Jewellery. An elegant cluster ring that features to the centre a rectangular tanzanite gemstone that measures 6x4mm (est 0. 50 carats) AAA colour. Complimented by an outer halo of sixteen small white diamonds , 1. 5mm each. Further seven diamonds per shoulder. Total diamond content estimated at 0. 45 carats. Colour i j, clarity Si. Head measures 9x8mm, depth 3. 4mm, weight 3. 6grams. UK hallmarks, no date letter, probably 2000 1010, all 18 carat white gold. Size O, we can resize free of charge.