Anvil
From Vintage Story Wiki
Anvils are vital to making better and higher tiers of metal tools.
To make an anvil you need to create an anvil mold via clayforming, then cast 900 units (9 ingots) worth of copper, tinbronze, bismuthbronze or iron into the mold.
Once an anvil is cast, you place it like any other block and use it for smithing metal tools from ingots heated in a forge.