A necklace of yellow and orange colored diamonds, a 239.7-grain (59.92 carat)natural pearl, and a 22-carat Burmese ruby are some of the star lots slated to go on the block at Christie's upcoming Dubai Sale, scheduled for April 20.

Other important pieces of jewelry appearing in what Christie's Head of Jewellery Middle East David Warren described as a "attractive and 'tailored' jewelry auction for our Middle Eastern collector" include a double-strand diamond necklace with a pre-sale value of $450,000-$550,000; a diamond ring whose stone is color graded Fancy Brownish Greenish Yellow and weighs 25.01 carats; and two rings set with cushion-cut Burmese rubies of 10.03 carats and 22.06 carats.

An eight-strand natural pearl necklace with a diamond clasp is estimated to sell for $240,000-$280,000, and a 30.05-carat sapphire and diamond ring by Van Cleef and Arpels is expected to fetch $80,000 to $120,000.