Peridotites rare earth elements

Assuming that half a percent liquid is trapped with the residue, equating the concentration in the rock to that in the solid residue will result in a severe bias for incompatible elements with Df<0.01 and in pure nonsense for elements with Dt<0.001. A typical example is represented by rare-earth elements in peridotites. Even separated clinopyroxenes can be suspected to have incorporated most of the REE from whichever trace amounts of liquid happened to be trapped in the cooling rock. If the rest of the minerals do not take any REE, it is left to the reader as an exercise to show that the concentration in clinopyroxene after uptake of incompatible elements is related to that in the clinopyroxene from a liquid-free residual peridotite through... 

Ottonello G., Piccardo G. B. and Ernst W. G. (1979). Petrogenesis of some Ligurian peridotites, II Rare earth element chemistry. Geochim. Cosmochim. Acta, 43 1273-1284. 

Loubet M., Shimizu N., and AUegre C. J. (1975) Rare earth elements in alpine peridotites. Contrib. Mineral. Petrol. 53, 1-12. 

McDonough W. F., Stosch H. G., and Ware N. G. (1992) Distribution of titanium and rare earth elements between peridotitic minerals. Contrib. Mineral. Petrol. 110, 321-328. 

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