For sale, a SUPERB Linde / Lindy 6-Star Deep Blue Sapphire, 18 Karat Yellow Gold Pendant with a 19 Inch 10 Karat Yellow Gold Necklace. Necklace Length: 19 Inches Hallmarks: 10K (10 Karat, Gold Quality, 41.67% pure gold), Designer Hallmarks which I could not identify - XL and a symbol in a circle. Thickness: 0.7 mm Weight: 0.54 Grams Pendant Length, including chain hoop: 12.6 mm / 0.5 Inch Width, widest point: 6.6 mm Thickness / Depth: 5.5 mm Hallmarks: Difficult to make out, on inside of chain hoop. Acid tested and confirmed 18 Karat (Gold Quality, 75% pure gold). Sapphire: Synthetic stone - Lab created.  Pear Shaped, 4 Prong held, measuring 8 mm long x 5 mm wide x 3 mm deep (1 Carat Weight). Deep Blue Color. The "star" only shows up under strong light. The "star" moves with the light. SUPERB stone. No scratches or chips. Weight: 0.92 Grams Combined weight of Pendant and Necklace: 1.46 Grams

An internet description of Linde / Lindy Star Sapphires:

In 1947, the Linde Air Products Company of New York began producing a form of synthetic gem corundum that was marketed in the gemstone industry as "Linde Star Sapphire." Also called Lindy stars, these laboratory-created gemstones were known for the perfection of their asterism, showing as a 6-pointed star under normal lighting. The Linde stars were sold as round and oval cabochons in various sizes and colors. Production of the Linde stars was discontinued in 1974 due to foreign competition.

If you ever wanted to get something special, this is it. A wonderful piece of art and high end value. Made with exquisite materials, this is sure to be a show stopper. It is elegant, classic and very rare. Perfect as the most gorgeous Christmas Gift, or for the collector of vintage and rare items, or the Gold investor. Can't go wrong with quality.