"Pseudoleucites" are rounded areas consisting of feldspar, nepheline, analcite, &c., which have the shape, composition and sometimes even the outward crystalline shape of leucite; they are probably pseudomorphs or paramorphs, which have developed from leucite because this mineral is not stable at ordinary temperatures and can be expected under favorable conditions to undergo spontaneous change into an aggregate of other minerals.Leucite is very often accompanied by nepheline, sodalite or nosean; other minerals which make their appearance with some frequency are melanite, garnet and melilite.