Japan's polished diamond imports increased 28.6% in January 2011, totaling 243,567 carats worth $72.4 million.

IDEX reports that the January import figures are back up to levels seen in the country's diamond trade prior to the financial crisis, with the volume matching January 2007 and the value of polished diamond imports equal to that seen in January 2008.

The per-carat value of polished diamond imports also increased in January, albeit by a more modest 11.9%, to $297.17.

Data from Momozawa & Co indicated that India was Japan's biggest supplier of polished diamonds – sending just under 200,000 carats of stones worth $33.1 million – followed by Belgium ($11 million worth of polished diamonds) and Israel.

While Israel's polished diamond exports to Japan were considerably lower than those of India and Belgium, the Israeli goods had an average per-carat value of $1,228.