There are several synonyms that can be used in place of the term "copperworks." Some potential options include "copper smelter," "copper refinery," "copper foundry," or simply "copper processing plant." Each of these terms could be used to describe a facility where copper ore is processed into a more usable form, such as copper ingots or copper wire. Depending on the specific context and industry, one of these synonyms may be a more appropriate term to use than "copperworks." By using these synonyms, writers can add variety to their language and avoid repeating the same term multiple times in a piece of writing.