Modernist color-change tourmaline ring, United States, circa 1960–1970, crafted in solid 18K gold and centered with a natural translucent blue?green cushion-cut color-changing tourmaline in four prongs (9.41 x 7.56 x 5.38mm; 3.07 ct). Accented by 12 well-matched round brilliant diamonds in flush four-prong settings totaling approx. 0.96 ctw (F color, VS clarity) for crisp contrast and sparkle. Weight 14.0g; size 7.75 (sizable); measures 21 x 16mm and rises 9mm. Stamped with maker’s mark, Spritzer & Fuhrmann retailer mark “S+F,” .750 gold marks, serial no. 34, and signed “S+F 18KT 34”. Very good conditions. All our diamonds and colored gemstones are naturally earth-mined. Any synthetic (lab-grown) stones will be clearly indicated in the description. Upon Request, Auction House may provide Ring resizing or/and appraisal. This will carry an additional cost. Appraisals are made by our in house GIA certified Gemologist.