A classical treasure group, at least in Germany, are those values hidden by the German Reichsbank (federal bank) and other institutions in the last days of the war. Several very valuable caches have been found by the US army. Other items are still missing, the famous amber room among them. The US used special „treasure squads“ to trace them.
This topic is covered by special literature, e.g. „Nazi Gold“ by Sayers. Even today treasure hunters try very carefully to find any hidden items. I think most Nazi Treasure hunters today will not find anything worth mentioning. Usually, in years and decades of tedious research they solve many small riddles but are unable to answer to most important question, where an object is located today. After more than 6 decades most trails today are cold. Those who knew hidden items had all occasions to remove them. The important people are long dead. Finally, those who find former property of the Third Reich in Germany will have to return it to the state. They are eligible for a 3% finders fee only. In the last decades no such finds became public.
To those who are after German World War 2 treasure I recommend contacting inhabitants of the former German east provinces, e.g. East Prussia. When these people were finally allowed to leave – much too late in winter 44/45 - they had very limited transport. Many of them even believed they would return soon. So they dug items before they fled the Russian army. Like so often, the small treasures few people know are more promising than the big ones.