Gold doesn't appreciate in value. It's an important distinction when considering investments. It tends to act as a store of value, that is it retains value. While the dollar price of gold goes up (now ~$2700 (!) as the dollar keeps imploding over time), that isn't the same as it appreciating in
value. The dollar is losing value, gold is what is staying still in terms of value. And while that isn't always perfectly accurate (certainly gold sometimes varies upwards or downwards in value for various supply etc reasons), it tends to be mostly correct.
The reason it's an important distinction is because eg the S&P500 will tend to smash gold over time as a value generative asset (because gold is not a productive, generative asset; gold holds value, the S&P500 generates value (profit/growth/etc)).