Does anyone know the real value of this coin?

Help trying to understand the real value of this coin including the rarity index

The real value is to you is whatever you can sell it for.  Have you looked in Numista?  You know it's 7.89 g of .999 gold.  Start with melt value as a minimum.  Find the Numista page for it and see if there's any resent sales.  

We will most definitely need a photo of the other side of the coin.

There are 11 gold coins listed for Russia in 2008.

The Numista rarity index is just an indicator of how many Numista users have registered the coin in their collection, not the actual minted scarcity of the coin.

...here is the other side of the coin. Thank you dear friend

As long as it's genuine, it's worth at least the bullion value of $513 USD (about €475).
I'd have to agree that it's worth whatever someone is willing to pay.  There are a couple of similar ones for sale on eBay right now for about $1100-$1300 USD (€1000-€1200), but that is just what the seller is asking for.  No recent sales though.

Check the recent sales on the Numista coin page. Most are pretty close to melt value. 

Nice.  similar to a sovereign. 

https://www.acsearch.info/search.html?id=10882570

Sold for 450 euros.

OK people my thanks to all of you 🙂cheer's