Building weath kinda sucks.

[Wulf38]

With currency you get the option of converting 10% of a city's hammers into gold. The problem with this is that for the vast majority of cities, 10% of their hammers = 0 gold per turn. It could probably use a buff to 25% like for building research.

 

[SdrawkcaB]

Agreed, it is currently useless even in a city with a market, bank, etc