Ashlar

Ashlar stands apart from fieldstone and rubble because the stone itself is squared up before it ever goes in the wall, either as coursed ashlar, where each row is a uniform height, or random ashlar, where block sizes vary but every face is still cut flat and square. That precision lets a mason set thinner, more consistent mortar joints and gives the finished wall a clean, formal, architectural look that reads very differently from a rustic rubble or fieldstone surface, even when the underlying stone is quarried from the same source. Corners and edges on ashlar are usually squared off separately so the wall reads as crisp from every angle, not just straight on.

Cutting and dressing stone to that tolerance takes more time and skill than fitting rough fieldstone, so ashlar tends to show up on entries, pillars, and facades where the client wants a more refined finish rather than a rustic one. It's less common in the Blue Ridge foothills than rubble or fieldstone simply because of the extra labor involved, but it holds up the same as any properly built stone wall does once it's set on a proper footing and pointed with the right mortar. For clients weighing a formal look against a rustic one, ashlar and fieldstone are really two different design decisions built on the same underlying structural rules, not two different levels of durability.