But more modern builders stopped using copper and copper alloys. They cost more than other building materials.
但是现代建筑师已不再用铜和铜合金，因为它们比其他建筑材料都要贵。
VOA Special 2016年2月合集
Keevil says earlier generations of builders in the United States also knew this about copper. That is why copper alloys such as brass were often used in building materials.
Copper alloys are metal alloys that have copper as their principal component. They have high resistance against corrosion. The best known traditional types are bronze, where tin is a significant addition, and brass, using zinc instead. Both these are imprecise terms, both having been commonly referred to as lattens in the past. Today the term copper alloy tends to be substituted, especially by museums.