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The magnetic recordings preserved in calcite speleothems and the nature of their constituent magnetic minerals hold enormous potential for paleomagnetic and paleoenvironmental reconstructions. Speleothems lock magnetization in instantly, are not affected by post-depositional effects, and can be dated with high precision. The natural remanence in speleothems is carried mainly by magnetite, and the main remanence acquisition mechanism is depositional, through physical alignment of detrital magnetic grains parallel to the Earth’s magnetic field. Detrital particles are deposited on speleothem surfaces either from receding flood waters, or directly from drip water percolating through overlying rock and soil. Chemical remanence, acquired in situ by particles growing through a critical volume, is of secondary importance. Previous studies of speleothem magnetism have shown that geomagnetic features are …