1 Ecu-Louis XV

Very new at this, but what does bullion value mean?  if the Numista Rarity index is 83, just how rare is that?  I have a 1768 and would like to know what the current value is before I put it in my safer deposit box.  Can someone advise?

http://www.ngccoin.com/poplookup/World-Coin-Price-Guide.aspx

   Welcome to the site - that link has prices on there.  

http://www.ngccoin.com/poplookup/WorldCoinPrices.aspx?category=76050&worldcoinid=209265&FromSearch=true
   That is one of the 15 links for your coin. On there I filled in four parts >
Country: FRANCE   Region: All Regions   Denomination: ECU   Date: 1768

   Bullion value means there is a formula relating to the % of precious metal in the coin and the current bullion price of that metal - so shows what the scrap value of that coin is.
   The Rarity Index is a rough guide to the scarcity of the coin, and is based on how many members have entered it in their collection or exchanges. So nobody owning a coin is 100 then it goes down to 98 then gradually by lower numbers. So 83 means about 20 members have it.

Hello,

I've got the valuation catalog for royal french coins, could you post a photo and I will make an estimation. What is the mint?

Thanks.