US net imports of polished diamonds for January 2011 totaled 375,304 carats worth $326.2 million, a 20.5% increase over the corresponding month of 2010, the US Chamber of Commerce reported this week.

Gross polished imports were up 6.3% by value and 3.6% by volume compared to January 2008, prior to the advent of the global financial crisis. Net imports, however, comprised only 33.7% of the net polished imports of January 2008. The volume of the imports increased 109.8% over January 2008, dropping the average per-carat value from $5,417.71 in January 2008 to $869.19 in January 2011.

In gross terms, imports of 1.17 million carats valued at $1.59 billion represented an 8.8% increase by volume and a 24.8% increase in value over January 2010, and a 14.7% increase in the average per-carat value to $1.356.53.

Israel led the list of diamond exporters to the US, shipping 215,154 carats of polished diamond worth $746.8 million in the month of January – 47% of the US's polished diamond imports by value. India supplied 70% of the US's polished diamond imports by volume, shipping 820,176 carats with a combined value of $405.1 million.

US diamond exports for the month reported totaled over 796,000 carats with a value of $1.26 billion. Israel, India, and Belgium led the list of diamond trading centers that received diamonds from the US.