YouTube rewards channels for how many subscribers they have. Passing 100,000, gets you a Silver Play Button award. But seven months after hitting that benchmark, Cody from Cody's Lab got tired of waiting for YouTube to send him one and decided to make his own.
Cody spends a lot of time on his channel doing science experiments "from scratch": turning pee into gunpowder, extracting iodine from seaweed, and refining precious metals. With lots of the stuff already laying around, he cast the button out of pure silver in a clay mould. For contrast, the official award — as torn down by AvE — seems to be some combination of tin, zinc, and nickel. While Cody hasn't quite reached the 1 million subscriber mark that would merit a Gold Play Button, he made the center of his award out of, again, actual gold.
Congrats again Cody and please don't hit 1 million — the award you'd have to make might cause you to bankrupt yourself.