Commercially pure materials, usually metals, are ones that have been purified to a practical extent, sufficient for commercial purposes; that is, they are close to absolute/theoretical purity albeit with some low-but-nonzero tolerance for impurities (such as trace metals) that allows for their economically viable production cost.
Major examples include: Commercially pure titanium: see Titanium § Commercially pure titanium Commercially pure zinc: see Zinc § Commercially pure zinc Commercially pure aluminium: see Aluminium § Applications
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