Some of the other more common rare earth carbonates are ancylite , carbocernaite , synchysite , tengerite , parisite , lanthanite , ewaldite , burbankite , donnayite and bastnasite . Cordylite was first discovered at the famous mineral site of Narsarsuk , Greenland and is only found as small crystals that can be used for micromounts. Cordylite is found in carbonatites, alkaline syenites and zeolite veins. It is a rare mineral as it is known from only a few localities and then not in large amounts. Luster is greasy to adamantine.
Crystals are translucent to transparent, some specimens approach opaqueness.
Crystal System is hexagonal. Crystal Habits include small prismatic or platy crystals, some demonstrating a hemimorphic character. Fracture is conchoidal. Streak is white. Notable Occurrences include the type locality of Narsarsuk , Greenland.