This is brass from melted down shell casings.
gold doesn't tarnish, you simple minded halfwit.
https://www.reddit.com/r/interestingasfuck/comments/18ixk48/a_us_soldier_standing_in_a_truckload_of_captured/#lightbox
This is a photo of "gold" stored in Fort Knox.
24 carat gold is EXACTLY the same color, and IT DOES NOT TARNISH.
Everyone of these gold bars is fake brass, none of this is gold.