The Dashankeng gneiss located in the northeastern Dabie mountains is composed mainly of potassium feldspar, plagioclase and quartz with minor hornblende, biotite and allanite, belonging to monzonitic granitic in composition. 北大别东部大山坑片麻岩主要由钾长石、长石和石英组成,少量角闪石、云母和褐帘石,成分为二长花岗质。
Allanite \Al"lan*ite\, n. [From T. Allan, who first distinguished it as a species.] (min.) A silicate containing a large amount of cerium. It is usually black in color, opaque, and is related to epidote in form and composition.