What elements are created by the violence of the supernova explosion itself?

Elements heavier than iron via rapid neutron capture processes.

While a star synthesizes lighter elements throughout its life via core burning, the creation of the heaviest elements is intrinsically linked to the explosive environment of the supernova. The extreme conditions present during the core collapse and subsequent Type II Supernova explosion provide the necessary environment—including a massive flux of neutrons—for rapid neutron capture processes to occur. These processes are responsible for synthesizing elements that possess atomic masses greater than iron, such as highly valuable substances like gold, silver, and radioactive elements like uranium, which are then scattered into the interstellar medium as part of the supernova ejecta cloud.