Stone Masonry – What do you call finely dressed stones laid in lime or cement? In building construction terminology, identify the class of stone masonry in which stones are carefully cut and finely dressed, and then laid in lime or cement mortar to form regular courses and tight joints.

Introduction / Context:
A key classification in stone work is based on how well stones are finished and how they are laid. From rough irregular stones to precision-cut blocks, the category chosen affects strength, appearance, cost, and speed of construction. This item tests recognition of the term used when stones are finely dressed and laid in mortar for high-quality work.

Given Data / Assumptions:

• Stones are finely dressed (accurately cut to shape and size).
• Laid in lime or cement mortar (not dry-laid).
• Regular courses and tight joints are intended.

Concept / Approach:

Ashlar masonry uses accurately cut stones with true faces and right angles, producing thin mortar joints and a refined finish. Rubble masonry (random or coursed) uses undressed or roughly dressed stones. Dry rubble omits mortar entirely, relying on interlocking and gravity. Therefore, once finely dressed blocks are laid in mortar, the correct classification is ashlar masonry.

Step-by-Step Solution:

Verification / Alternative check:

Standard building construction texts list ashlar work (plain, chamfered, rusticated, etc.) as the premium category with thin joints (often 3–6 mm) and regular courses.

Why Other Options Are Wrong:

Random/coursed rubble use irregular stones with thicker joints; dry rubble omits mortar; polygonal refers to random sided faces, not finely squared ashlar.

Common Pitfalls:

Confusing well-coursed rubble with ashlar; assuming any mortared stonework is ashlar even when stones are not truly dressed.

Final Answer:

Ashlar masonry