9ct White Gold Tanzanite 6x4mm Pear Rub Over Set Stud Earrings. 03-20-355. These simple 9ct White Gold and Tanzanite stud earrings are completed by post and butterfly fittings. Wear as a single pair or mix with other pieces from our Essentials collection to create the perfect stacking look.  We have an expert team of gemstone specialists who handpick and grade each jewel to meet our high standards and a team of talented in house designers who combine their talents to bring you our exclusive Precious Gemstone collection. You can find matching items online and in our stores. All articles are lovingly and securely dispatched with our elegant jewellery packaging.