Oolitic limestone of Manassas (Triassic) age occurs in a quarry near Culpeper, Virginia. Limestones are rare in the Virginia Triassic, and no other oolitic occurrences are known in this area. The major constituent of the rock is primary calcite; whereas illite, chlorite, and talc predominate in the insoluble residue. The heavy minerals as a group appear to be nondiagnostic as to provenance. However, the characteristics of the detrital tourmaline suggest an eastern source. The oolitic limestone apparently represents deposition in a fresh-water lake of limited areal extent. Shallow water deposition is indicated by well developed mudcracks, and minor disconformities within the bed.