Featured in this lot is this excellent ribbon, 6.64ct tanzanite, diamond, and platinum ring with AIGL paperwork. This ring shows a polished, stamped, and tested platinum ring with a bright finish. The ring is in new condition and displays excellent workmanship and an 'Orianne' hallmark with a PT950 stamp next to the hallmark. The center stone is a natural oval brilliant cut pavilion tanzanite stone with measurements of 13mm x 10.8mm x 6.8mm, a total weight of 6.64 carats, coloration of violetish blue, and a very good cut grade. Tanzanite is a very rare precious gemstone that is only found in the Usumburu Mountains that border the Umba Valley of northern Tanzania. It was originally discovered in 1967 by Tiffany & Company, who named the stone Tanzanite. This example is unique due to its exceptional pleochroism (an optical phenomenon in which a stone has different colors when observed at different angles). The center stone and ribbon shoulders are lavishly decorated with 74 round brilliant diamonds and include measurements of 2.5mm x 1.5mm - 1mm for the 4 baguette diamonds and 1.1mm - 2.0mm for the 70 round cut diamonds; the diamonds have a collective weight of 1.08 carats, a color gradient of F – G, and a clarity grade of VS1 - SI1. The piece comes complete with AIGL Inc. (American International Gemological Laboratories, Inc. a GIA certified lab AIGL#: K79E99-EA13288) report and appraisal, confirming the above info and giving a total value of $19,847.00. The ring size is US 7 1/4.