K-feldspar forms among the largest crystals in the leucogranites and contains all the other phases as inclusions. They are thus the last phase to crystallize. Muscovite is always present partly as large flakes, but its abundance decreases from the biotite facies to the tourmaline facies leucogranites. This mineral is evenly distributed throughout the granite and can be found as inclusions within plagioclase, quartz or K-feldspar. In the biotite facies, both phyllosilicates are intimately intergrown without enclosing relationships.
Tourmaline shows colour zoning from lavender blue to yellow-brown.
The blue colour is generally, but not necessarily, restricted to the core of the crystals. This phase is usually euhedral although it sometimes shows a skeletal habit. Accessory phases in both leucogranitic types are apatite, monazite, ilmenite, zircons beryl and copper mineralisations. In one aplitic sample of the Reru valley, fuchsite was observed as the dominant phyllosilicate. Pegmatites and aplites belong to the tourmaline facies because they have all the mineralogical characteristics of this category of leucogranites.