The volume of Japan's diamond trade rose in September 2010, with the country recording 30% more polished diamond imports, a total of $72.4 million, Diamond World reported on Sunday.

In terms of volume, the increase in diamond trading consisted of 285,098 carats, with the per-carat price of polished diamonds dropping to $254.

India led the pack of polished diamond suppliers, exporting some 165,023 carats-worth of polished diamonds to Japanese diamond companies at $31.9 million. Next in line was Belgium, which supplied Japan's diamond suppliers with polished diamonds worth $14.2 million in September.