Tiffany & Co. Melo Melo Pearl & Diamond Necklace. photo courtesy M.S.Rau Antiques

This exquisite necklace by Tiffany & Co. showcases a rare melo melo pearl. A diamond-studded platinum chain complements the pearl's porcelain orange hue. The yellow and white round-cut diamonds weigh 6.50 total carats. The necklace is secured by a diamond-studded box clasp. Signed "Tiffany & Co."in two places, and marked "PT 950". Pearl: 23mm; 18" length - Price: $300,000

A work of art by Tiffany & Co., this magnificent necklace showcases a rare melo melo pearl, one of the most exceptional pearls in the world. Exhibiting an almost perfectly round shape and the highly desirable orange hue, this pearl is suspended from a platinum chain dotted with 6.50 carats of yellow and white diamonds and held securely by a diamond-studded box clasp.

An Asian passion with a long history of veneration, the extremely rare melo melo pearl is formed by the Melo Melo, or Indian volute snail, which inhabits the waters of Southeast Asia. Like conch pearls, the melo melo gem is not actually a nacreous pearl because it contains no nacre. Instead, it is classified as being "porcelaneous" in appearance. Ranging in color from tan to dark brown, with orange being the most desirable color, melo melo pearls are extremely large and generally very round, and all are natural, as attempts to culture them have failed so far. Although these pearls have been known and collected in Asia for many years, they have only recently been introduced into the West, and have been know to set record prices at auction.

M.S. RAU ANTIQUES. www.rauantiques.com