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The anhysteretic remanent magnetization (ARM) is a laboratory-imparted artificial remanence that is used widely in mineral magnetic studies (Dunlop & Özdemir, 1997). An ARM is usually imparted by exposing a sample to an alternating field (AF; e.g., ∼100 mT) with a superimposed small direct current (DC; e.g., ∼50 μT) bias field. The bulk ARM is given as the sum of the ARM of each component (Egli, 2004a(Egli, , 2004bFabian & Leonhardt, 2009):where M ar is the bulk ARM imparted with a DC field H dc for a sample containing N magnetic components with saturation remanence M rs and component-specific ARM ratios, 𝐴𝐴 𝜘𝜘𝑖𝑖 = 𝜒𝜒𝑎𝑎𝑖𝑖∕𝑀𝑀𝑟𝑟𝑟𝑟𝑖𝑖 , where 𝐴𝐴 𝜘𝜘𝑖𝑖 is the ratio of the ARM