Originally posted by Chuck:

jumping onto a stone hearth should damage it. And also it sounds like metal when you land on it.

Campfires and hearths were nerfed and made to take damage, to keep people from using them as weapons against mobs, as many people were placing dozens of fires down to fight enemies and bosses such as Elder.... It was an unintended mechanic of fires that was getting exploited, so the devs "fixed" it.