You can tell by looking at this piece that it is of modern origin. The likely date in 1989, the 100th anniversary of Hitler's birth. I've seen these in both brass and what looks like silver, although I have been unable to ascertain for sure if the silver ones are pure silver. They may be plain white metal, and probably are.
A related bronze medal dated 1933 with the slogan ein volk, ein reich, ein fuhrer (one people, one empire, one leader) appears at this CoinQuest link [click here] and is worth upwards of $200 US dollars. This piece, however, is worth much less.
Evaluating these medals is difficult. The best we can do at CoinQuest is to hypothesize that pure silver specimens were manufactured somewhere in Germany around 1989 but these were soon gone (purchased or stashed) due to displeasure with the subject. Then, sometime later, an enterprising individual started making look-alikes in white and gold-colored base metal which ran on eBay and similar sites for a while. The medals in our pictures are in the look-alike category. From their eBay data, they sell roughly as follows:
worn: $5 US dollars approximate catalog value
average circulated: $10
well preserved: $20
fully uncirculated: $40