925 Solid Sterling Silver 4.5ct Midnight Blue Genuine Natural Sapphire Size 6 Ring This Listing Is For 1 Natural Genuine Dark Midnight Blue color Sapphire Classic Engagement / Cocktail Ring. Size 6. Similar in design to Princess Diana / Kate Middleton sapphire ring. 100% natural stone mined from the earth, not synthetic or lab created. Estimated Sapphire weight is 4.50 carats. Oval shape sapphire measures 11x9mm. This sapphire is surrounded by AAA grade machine cut sparkling czs. Top Width measures 16mm = 0.63". Solid Sterling Silver: Rhodium plated to retard tarnish and always shine. Stamped 925. Looking for a gift a unique woman you love? These beauties are gift boxed and ready for giving. Something you can feel great giving and know the recipient will be thrilled for receiving them from you.