In article , "John
G" says...
I have an old blacksmith's anvil, which through lack of use in a damp
atmosphere has become rusty

What would be a good way of restoring it? Sandblasting?

It might make an interesting coffee table base, or garden seat.

Stick it in a tub of acid - sulphuric will dissolve the rust,
phosphoric will convert it to a stable black compound which provides
a degree of protection from further corrosion.