Rough diamonds are expected to become costlier next year, according to James Allen. The reason is the gap generating between the rising demand of diamond jewellery at 6% per year, and supply increasing only by 1% annually.

The volume of diamond output worldwide, is estimated to reduce from $12.8 billion of 2006, to $12.65 billion in 2007. This is turn would affect jewellery to become more expensive. Allan mentioned that fall off of grades at De Beers' Jwaneng mine in Botswana was largely responsible for the decline in supply.