What is a Quoin in Architecture?
A quoin is the decorative block of stone or brick that is placed at a corner of a building to accentuate its corner. Quoins can be either decorative or structural. They are characteristically different than the materiality of the adjoining walls. Quoins are also usually arranged in a toothed manner with alternate quoins that project and recede.
The Return Quoin, Reveal Quoin, Chamfered Quoin, and Cladding Quoins are all multiple types of quoins.