I recently acquired a gorgeous, high relief medal. A similar one sold on Heritage in 2006 (Auction 419 Lot 51684), same reverse design (personifications of Theology, Philosophy, Medicine, Law) but it had Wilhelm I on the obverse, not Wilhelm IV as this one does. Apparently this was some sort of series, with reverse design by Pfeuffer and Obverse (bust) by Jachtman. I found what may be a reference to this specific medal on numismatics.org (the American Numismatic Society websites) - Accession# 1967.225.311 but although the diameter of 42.5 mm agrees with mine, the weight they give of 42.58 g doesn't (mine is 69.9 g - same as the Heritage similar example) and they list material as "B" (they don't define what "B" is) and mine appears to be a high alloy of Gold (may be 24 kt). If you know anything about this medal, or this series, your information would be greatly appreciated. I am specifically looking to verify it's Gold content, place and date of mintage, and something about this (apparent) series (who sponsored it, etc).
Friedrich Wilhelm IV, King of Prussia in 1871 was inthronised as (all-)German Kaiser under the name Wilhelm I