Britain, whose troops are facing the rebel movement in Sierra Leone, is particularly keen to stem the trade from that country, where at present the government controls not a single diamond.

ECONOMIST: How to stop diamonds paying for nasty African wars

Experts say it has since been determined that they were cut from a single pink diamond weighing 242 carats.

BBC: Princie Diamond: Rare Indian gem sells for $39m

She burst into the music charts in 2009 when she featured on the Diamond Rings single by rapper Chipmonk.

BBC: Brit Awards: Emeli Sande wins two awards

Albany leaders, who have discretion over some federal money, shifted some federal funds to family shelters and limited how much it would pay for single adults, said Seth Diamond, the city's commissioner for the Department of Homeless Services.

WSJ: Homeless Costs Shifted

The researchers tried three ideas: a single tungsten tip, an array of silicon tips, and a film containing jagged fragments of synthetic diamond, whose sharp angles acted as tips.

ECONOMIST: Medical technology