This is the type locality for this rare earth mineral. It is one of three localities worldwide. The Perrierite is lanthanum bearing and can be seen on this specimen as black crystal grains to 1mm. It is associated with Microcline, Zircon, and garnet. The host rock is a syenite defined as a magmatic deposit containing less than 5% Quartz and is peralkaline (rich in K, poor in Ca).
Lanthanum was discovered in 1839 by the Swedish chemist, Carl Gustav Mosander. It is used for specialy glass, lighting, and hybrid car batteries.