The yellow-brown diamond in a fire rose cushion cut was purchased from De Beers by a group led by Henry Ho of Thailand and given to Thai King Bhumibol Adulyadej in honor of his 50th coronation anniversary.

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Then he discovered a new Japanese method of cutting diamonds: When viewed under a low-magnification (3x) lens, the stone refracted light in such a way as to give off a pattern of eight heart-shaped sparkles at the bottom of the diamond and eight arrow-shaped fire-bursts through the top--hence the name "hearts-and-arrows" diamonds.

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