> Gold only has value because people believe it has value. It's also somewhat volatile and not immune to bubbles.

Gold and silver don't really have bubbles, they are kind of anti-bubbles. When it seems the music is about to stop in the musical chairs of the world economy, people pay a premium for precious metals because they feel safe in that they have value. Bubbles tend to happen in a go-go economy, precious metals become temporarily overpriced when people are worried about the world economy. Like the era when the Hunt brothers were buying silver.