Once copper has been smelted to blister copper or refined to unwrought copper, it leaves heading 2603 and falls under the chapter covering copper and articles thereof. Concentrates are beneficiated ore that still require smelting; the key distinction is whether the metal has been reduced from its sulfide or oxide form.

Chile holds some of the world's largest porphyry copper deposits and has long-established export infrastructure, making it the primary global concentrate supplier. Canada's proximity and integrated North American mining industry make it a natural secondary source, with shorter logistics chains to US smelters.