Depending on which index one follows, polished diamond prices either rose (RapNet) or fell (IDEX) slightly in January. IDEX writes that, "Restocking following the holiday season failed to stimulate an increase in polished diamond prices in January," but "January’s very slight slide provides hope that a corner has been turned." Meanwhile, Rapaport writes that, "Polished diamond prices rose in January as shortages continue to support the market. U.S. demand is steady after a reasonably good holiday season, while China’s wholesale market slowed as the focus shifted to retail for the Chinese New Year Spring Festival starting on February 8." The RapNet Diamond Index (RAPI™) for 1-carat, GIA-graded diamonds rose 0.9% in January. RAPI for 0.30-carat diamonds advanced 4.7% and RAPI for 0.50-carat diamonds grew 4.5%. RAPI for 3-carat diamonds fell 0.5%. RAPI for 1-carat diamonds fell 4.4 percent from a year ago as manufacturers sought to reduce excess inventory in 2015.
Most notably, Rapaport states that its "Rapaport Monthly Report demonstrates that polished prices rose in January due to shortages rather than increasing diamond demand. Polished trading was driven by U.S. jewelers replenishing stock sold during the holiday season as well as some inventory purchases. However, uncertainty remains as consumer demand is sluggish in emerging markets. The stronger U.S. dollar is negatively impacting tourist spending in the U.S. and domestic dealer demand in India and China ... Diamond market sentiment improved during January and dealers feel that the worst may be over."