Recall from Warren Buffett's 2011 letter to investors:
Today the world’s gold stock is about 170,000 metric tons. If all of this gold were melded together, it would form a cube of about 68 feet per side. (Picture it fitting comfortably within a baseball infield.) At $1,750 per ounce – gold’s price as I write this – its value would be $9.6 trillion....You can fondle the cube, but it will not respond.
Below is what said gold cube containing all the world's gold would look like, with distinctions for the various types of gold currently in existence: