Beautiful SILVER 1950-D/S Mint Mark Error Coin Very Rare

I was lucky enough to find this GEM when I purchased a lot of 25 SILVER Quarters from someone on E-bay and didn't even know about the Mint Mark error until I read about it recently. I checked the coin and sure enough you can see the D Mint Mark stamped over the S Mint Mark and the coin is in Pristine condition. I still have to get it authenticated however.. I will update this post and put it up for auction as soon as I get it authenticated and graded by NGC or PCGS.