Hello,often in the open market area of Athens i meet sellers that sell the coin of the photo of En Numista (Brilliant Silver)50euros.Good price for a coin.
Now your coin definetely not look for a silver coin.
In my opinion is Silver alloy- 50% silver/50%copper,thats why the collor of the patina near to brown.
Not fake from nowdays,because there is no interest for coins from Islamic states.
Probably imittation of the past or with the years change the purity of the silver for economical reasons.
Rare version of the coin.Really interesting.
If it pass the magnet test is sure silver alloy.
I would like to see an example

5 Para - Abdülhamid II 1901.The coin turn to green from big precent of copper.
After all i believe that price of the specific coin higher from 50euros.
Regards.