Can You Solve this Ice Diamond Riddle? ft. Vsauce’s Michael Stevens

Isn't this basically the same puzzle as the one with the rock in the boat on the lake? When the diamond floats it displaces water according to it's weight and when it sinks it replaces water according to it's volume. Because the density of the diamond is higher than the water's, it displaces more water when it's floating and the water level will sink after it melts.