ARGYLE Diamonds offered its largest ever polished pink diamond for sale at its annual Pink Diamond Tender, this week 10 years ago. The cushion cut gem weighed in at 3.66 carats and was one of two diamonds in the collection weighing more than three carats. Sales manager David Fardon said more than 500 diamonds had been offered for sale since the tender was launched in 1995 and only six three-carat plus diamonds had been presented out of that total. Argyle’s 1995 collection sold for over $US4.5 million, at an average price of over $US100,000 per carat. Pink diamonds form less than 0.1 per cent of Argyle’s annual output of about 35 million carats.