The picture in the link is that of a fully functioning solid gold WC, made by Italian artist Maurizio Cattelan. It is made of 18-karat gold.
How can one use such a gleaming gold WC? The WC was on display at the Guggenheim for nearly a year, installed in a restroom for the private use of members of the public, with a guard posted outside. Without guard, I reckon, it will be stolen the very next day.
Cattelan said, "Whatever you eat, a $200 lunch or a $2 hot dog, the results are the same, toilet-wise." He is right.
Ironically, millions are without flushed toilets in developing countries – not made of gold, but of PVC!