There is a concentration of smelters, refineries, and foundries close to northern Belgium's copper mines because copper production is a bulk-reducing industry.
A bulk-reducing industry can be defined as a type of industry in which the raw materials (inputs) that are used for production weighs more than the finished good or final product.
This ultimately implies that, a bulk-reducing industry such as copper mines are established close to smelters, refineries, and foundries because they make use of raw materials that weigh more than the finished good or final product.
Read more on bulk-reducing industry here: https://brainly.com/question/26779067
