Ashlar

 ( Building Stone ) 

Ashlar masonry is in contrast to rubble masonry, which employs irregularly shaped stones, such as flat ledge or rounded river or lake stones, sometimes minimally worked or selected for similar size, or both. Ashlar masonry is related but from other stone masonry that is finely dressed but not quadrilateral, such as curvilinear and polygonal masonry.

Ashlar masonry may be coursed, with stone blocks laid in continuous horizontal layers. Ashlar may also be random, which involves stone blocks laid with deliberately discontinuous courses, interrupted both vertically and horizontally, as in snecked masonry. In either case it is generally joined with a bonding material such as mortar, although dry stone ashlar construction is found, and metal ties and other methods of assembly have been used. The dry ashlar of Inca architecture in Cusco and Machu Picchu is particularly fine and famous.

In tile carpet installation "ashlar" refers to a vertical 1/2 offset pattern.

In classical architecture, ashlar wall surfaces were often contrasted with rustication, each employing different chisels and techniques.

The term is frequently used to describe the dressed stone work of prehistoric Greece and Crete, although the dressed blocks are usually much larger than modern ashlar. For example, the Beehive tomb of Bronze Age Mycenae use ashlar masonry in the construction of the so-called "beehive" dome. This dome consists of finely cut ashlar blocks that decrease in size and terminate in a central capstone. These domes are not true domes, but are constructed using the corbel arch.

Ashlar masonry was also heavily used in the construction of palace facades on Crete, including Knossos and Phaistos. These constructions date to the MM III-LM Ib period, –1450 BC.

In large scale modern European construction ashlar blocks are generally about in height. When shorter than , they are usually called small ashlar.

• Ablaq
• Dimension stone
• Opus quadratum
• Stone veneer