The 'perfect pink' diamond
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Perfect pink diamond sells for $20.5m in Hong Kong

An extremely rare "perfect pink" 14-carat diamond has sold at auction in Hong Kong for more than $20m (£13m).

The diamond has a rectangular emerald cut - meaning it needed no additional facets to enhance its intense pink colour.

Christies jewellery specialist Mei Y Giam explained that pink diamonds over 10 carats are unusual in themselves, and the larger ones are usually "very light in colour".