By definition, occult artifacts are man-made objects that supposedly have occult (supernatural) powers. More specifically, these objects, if used “properly” (e.g. in proper occult ceremonies) allegedly provide their owners with supernatural (magical) powers.
There are speculations that some Nazis (first and foremost, SS Reichsfuhrer Heinrich Himmler) were actively hunting artifacts that allegedly (i.e. according to more or less well-known legends) possess occult powers.
Most of these claims are, indeed, speculations because they are not supported by any historical evidence. However, there are three objects that Nazis, indeed, were actively pursuing (one of them successfully). These objects were the Holy Lance (“Spear of Destiny”), Codex Aesinas and, of course, the Holy Grail.