Final Answer:
The cementitious material(s) in contemporary masonry mortar consist(s) of a mixture of Portland cement, lime, and sometimes additional additives.
Step-by-step explanation:
Contemporary masonry mortar is typically composed of a blend of Portland cement and lime as the primary cementitious materials. Portland cement provides strength and durability, while lime contributes to workability, water retention, and better adhesion. The ratio of these components can vary depending on specific project requirements. In addition to the main ingredients, various additives like plasticizers, air-entraining agents, or pozzolans may be included to modify specific properties of the mortar, such as setting time, workability, or resistance to environmental conditions. This combination of materials results in a versatile mortar suitable for different masonry applications, ensuring both strength and workability.