The RapNet Diamond Index for 1 ct. polished diamonds fell 1.8 percent to 94.18 in February, the online trading service announced.
The index for 0.30 ct. diamonds rose 3.6 percent to 16.04; the measurement for 0.50 ct. diamonds rose 0.9 percent to 34.81; and the average price for 3 ct. stones fell 2.1 percent to 343.32.
Regional influences have affected the pricing, a statement said, including increased rough supplies from the Marange diamond fields of Zimbabwe.
In India, the recent stability of the rupee has increased consumer confidence. The Hong Kong International Jewelry Show also revealed a steady demand for diamonds in the Far East region. However, fluctuating prices of diamonds and the uncertain economy continue to keep buyers cautious.