Alrosa will hold an online auction of rare investment-grade diamonds on April 23-25. Main lots will be 15 exceptional pink-purple diamonds that have been mined and cut in Russia over the past six years. Starting price of the most expensive pink diamond weighing 3.01 carats is estimated at $831 thousand. In addition, auction will be held offered an exceptional 30-carat round brilliant diamond with perfect cut quality - Triple Excellent.