Prystai will succeed Jonathan Price, who was appointed the chief executive officer earlier this year following the departure of company veteran Don Lindsay.
Russian billionaire Suleiman Kerimov and his family, which until earlier this year held a majority stake in Polyus, are set to face a fresh probe in France.
The fully-electric Jumbo will also break new ground in its user experience by reducing noise and vibration, and eliminating heat and the emissions of diesel particulate matter.