"Three main stages can be distinguished: (a) An epimagmatic-pegmatitoid stage during which the primary zonal development of the pegmatite body into border zone, wall zone, intermediate zones, and core was accomplished; (b) a hydrothermal replacement stage, divisible into a high temperature phase with a Li-replacement unit and a Cs-replacement unit, and a lower temperature phase with a cleavelandite replacement unit and a feebly developed fluorite unit; (c) a final stage of supergene alteration. The age of the pegmatite lies between 1650 and 1800 million years."

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