The present invention relates to the PVD coated tungsten carbide (WC) based cemented cutting inserts with ruthenium (Ru) as a key chemical element, or a key feature, in the cobalt (Co)-based binder phase, particularly useful for machining today's mold & die materials. In the Ru--Co mixed binder phase in the tungsten carbide substrate, the ratio of Ru/Co is at least 3%, by weight. The Ru-featured carbide cutting insert provided in this invention is PVD coated with one or more layers by a modern PVD coating technology. The development of the PVD coated Ru-featured carbide cutting inserts provided in this invention is based on a discovery that the unique combination of PVD coating techniques and Ru-featured carbide cutting inserts demonstrates superior machining performance in today's mold & die machining applications.