How much potassium is in the crust?

. New experimental data reported here for partitioning of potassium (K) between peridotitic silicate melt and Fe-Ni-S-C-O molten alloy at 1650-2200 °C and 1.0-7.7 GPa reveal a negligible effect of pressure on K partitioning, at least up to 7.7 GPa.