Assignment of igneous rocks to lamproite: major- and trace-element criteria and implications for the history of the Tomtor pluton (northwestern Yakutia)

The paper presents objections against assigning picritic and some other igneous rocks to lamproite as suggested by N.V. Vladykin, both in general and in particular for the case of the large Tomtor pluton of alkaline and carbonatite rocks in northwestern Sakha Republic (Yakutia). Classifying the Tomtor picrites (picritic porphyry and its breccia-like varieties) as lamproite appears to be inconsistent with their chemistry, mineralogy, and geology. Discussed are errors and poorly proven postulates in the related publications by Vladykin, which contradict the available field data. (C) 2009, IGM, Siberian Branch of the RAS. Published by Elsevier B. V. All rights reserved.