Car Insurance Question: Would a policy cover this damage?

Let’s say you’re in a car and in the trunk is a box full of delicate plates properly stored. Someone rear ends you, and the plates get destroyed. Even through they were properly packed, they couldn’t handle the impact of the car. Would insurance only cover the car damage, or would the plates be covered as well?

I’m asking because I’m carrying something really delicate and expensive in my car and while I know the chances are slim to non that someone will hit me, I get paranoid and curious about stuff like this.