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It is shown that lattice preferred orientation analysis by neutron diffraction can be successfully applied in the case of rocks, and particularly in the case of quartzites. Neutron diffraction gonio-metry is a technique similar to X-ray goniometry, already applied to cubic metals and recently to materials of hexagonal symmetry such as titanium. The main advantage of this technique results from the low absorption coefficient of neutrons for most materials, provided that their hydrogen content is limited : the recording is thus performed directly in transmission, simplifying the corrections ; it also allows the use of large samples (<- 1 cm3) and is therefore suitable for the analysis of aggregates with a large grain size (- 1 mm). The samples studied come from a quartzite sequence deformed along the Main Central Thrust of Nepal. The {1120} and {1010} pole figures compare well with previous diagrams obtained by X-ray diffraction. The orientation distribution function has been calculated in the case of one sample using seven pole figures, and taking into account the trigonal lattice symmetry. It allows the calculation of the (0001) pole figure, which is similar to the diagram obtained by U-stage measurements on a limited number of grains. All the diagrams display monoclinic symmetry, the foliation and the linéation being in no way symmetry elements for the pole figures : this is a very common feature in naturally deformed quartzites (and other rocks) indicating that the plastic flow regime was not coaxial, i. e. displaying a simple shear component. Rolled titanium produces diagrams having similarities with quartzite ones but with a higher symmetry, the rolling process being globally a coaxial deformation process. In that case the foliation (rolling plane) and the linéation (rolling direction) are symmetry elements for the pole figures.