Despite the tsunami and earthquake that struck Japan on March 11, killing tens of thousands of people, Japan's imports of polished diamonds continue to rise.

Numbers published by Momozawa & Co put the value of Japan's total polished diamond imports for April 2011 at $95.7 million, a 56.8% increase over March and an 80.1% increase compared to April 2010. In volume terms, Japan imported 249,994 carats of polished diamonds, a 64.7% increase from March and nearly 40% more than in April 2010.

The average per-carat price of the country's diamond imports rose 28.9% from last year, reaching $382.83/carat.

India remains Japan's largest polished diamond supplier, followed by Belgium and Israel.

Polished diamond imports for January-April 2011 totaled $279.3 million by value, 23% higher than the same period in 2010.