One is an enamel, baroque pearl, diamond and gold brooch from around 1899-1901.

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Another piece, a gold brooch set with an ancient gold coin that pictures Philip II of Macedonia, has patterns made of diamonds, blue topazes, amethysts, peridots, and pink and red tourmalines.

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Queen Elizabeth II gave Mr Obama a red leather-bound volume entitled A Selection of Papers From the Royal Archives 1834-1897, signed photos of herself to several senior White House aides, and a brooch with gold leaves and coral flowers to First Lady Michelle Obama.

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Younger sister Margaret had a Belperron flower brooch made of gold and diamonds.

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Highlights include some wonderfully whimsical pieces, like a brooch in the shape of a flower whose gold petals are engraved with the words "yes" and "no" on either side.

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