The coin has gone up for auction here: https://www.greatcollections.com/Coin/1135643/2011-25-BTC-Casascius-Bitcoin-Gold-Plated-Coin-PCGS-MS-66-from-photo

I am a bit disappointed in their photo, and that they only listed BTC value with no indication of the forks or anything, but hopefully anyone bidding understands what it is.