Theo Fennell - A tanzanite and diamond dress ring in 18ct gold, featuring oval-shaped rose-cut tanzanite, approximately measures 14.4 x 11.0 x 6.8 mm, strongly pleochroic with intense purplish-blue body colour, set in collet and encircled with an array of brilliant-cut diamonds, engraved with knapweed flower sprays on sandblasted shoulders, tapered to a pointed shank, signed and London hallmarked '750' with maker's mark 'TF', 2011, ring head measures 18.7 x 15.7 mm, ring size O½, total weight of item 19.7 grams.