This piece of research was conducted to provide guidance and help to theconservation architects for the preparation of appropriate lime mortar for the conservation of stonemasonry. A comprehensive research and detailed examination of conservation works on significanthistoric monuments in Lahore was carried out in the Department of Archaeology and Museums,Pakistan. The results provided the analytical description of lime, types of lime and preparation ofKankar-lime followed by description and analysis of various compositions of lime mortars suggestedby International and National experts of conservation. The mortars for conservation and repair workshould include the same range and a type of aggregate particles was used in the original mortar. Moreparticularly the original binder and pouzzolanic additives must be used. This must be ensured that newmortar should necessarily perform and appear in the same manner as the older performed andappeared.