What ingredient is not typically found in masonry mortar?

Masonry mortar is primarily composed of a mixture designed to bind bricks or stones together in construction. The common ingredients include sand, hydrated lime, and Portland cement.

Sand provides bulk and helps to form a workable mixture, while Portland cement acts as the primary binder that gives strength to the mortar. Hydrated lime is often added to improve workability and adhesion, and it can enhance the durability of the mortar over time.

Brick dust, while it may be used in specific applications for aesthetic purposes or to achieve particular properties in some types of mortar, is not a standard ingredient in typical masonry mortar recipes. Thus, its absence in a standard mortar formulation makes it the correct answer to the question of which ingredient is not typically found in masonry mortar.