The Loe-Shilman carbonatite complex is the western extension of about 200 km long belt of alkaline rocks. The alkaline belt is situated on the northern side of the Peshawar Plain in an arcuate fashion. It consists of sill-like bodies of carbonatite and related alkaline rocks. These sill like-bodies have been emplaced along a fault zone in metasedimentary rocks of Palaeozoic to Precambrian age. Using petrographic techniques, the sedimentary and metasedimentary carbonate country rocks of the Loe-Shilman carbonatites were classified as dolomite and dolomitic limestone, while the carbonatites were classified into (a) calcite-carbonatites and (b) dolomite-carbonatites. The carbonatites were also classified into (a) calcio-carbonatites, (b) magnesio-carbonatites and (c) ferro-carbonatites on the basis of geochemical data. Field relationships, petrography and geochemical data indicate that carbonatite magma originated by direct melting of the partly carbonated, metasomatized mantle peridotites. Calcite-carbonatite, the most wide spread variety of the carbonatites in the complex, appears to represent the first phase of carbonatitic magmatic activity, followed by dolomite (and ferroan dolomite)-carbonatite as a separate intrusion. Fission track dating on apatite crystals indicates that emplacement of the carbonatites took place probably in the Oligocene (30.0 ± 1.5 Ma)