Beginners treat the anvil like a surface. It's not. It's a rebound — a good anvil throws your hammer back at you so half the energy of every strike goes into the work for free.

The test

Drop a ball bearing from 30cm. It should spring nearly back to your hand. If it thuds, the anvil is dead — soft, cracked, or a cheap casting that looks the part and does none of the work.

What it changes

On a dead anvil you swing harder and tire faster. On a live one the work moves itself. It's the single biggest upgrade most shops can make, and it's the first thing I tell anyone building a forge.