A method of manufacturing a solvent extraction settler comprises manufacturing at the site of manufacture, such as in an engineering workshop, a plurality of self-supporting settler element modules (2, 3, 4, 5) each having exterior dimensions, strength and handling and securing means (6) conforming to shipping container standards, transporting the modules (2, 3, 4, 5) to the site of installation as normal freight by transport equipment, such as trucks, trailers and container ships, capable of handling and transporting shipping container standard compatible units, and assembling the modules (2, 3, 4, 5) into a complete settler at the site of installation. The settler comprises a module group (1) consisting of a plurality of self-supporting settler element modules (2, 3, 4, 5) each having exterior dimensions, strength and handling and securing means (6) conforming to ISO shipping container standards to enable ISO compatible transportability.