Henan Huanghe Whirlwind (600172), a producer of synthetic diamonds, posted a 189.3 percent year-on-year rise in first half 2011 net profit attributable to shareholders to 62.97 million yuan, with earnings per share of 0.2223 yuan, reports 163.com, citing a company filing.

Revenue increased 35.1 percent to 494.54 million yuan.

The company attributed the increased profits to higher sales of ultrahard materials, ultrahard compound materials, and finely dividend metals.

In addition, the write-back of impairment for certain assets and investment returns contributed significantly to earnings.