Horizontal mills, sometimes called Norse mills or tide mills depending on context, were among the earliest and most widespread milling technologies in early medieval Ireland. Unlike the vertical-wheeled mills familiar from later centuries, a horizontal mill placed its wheel flat in the water, driving the millstone directly above without the need for gearing. They were simple, robust, and suited to fast-running streams.

The Desert mill sits on the western side of a small stream, just east of the local church and its associated graveyard, a clustering of features that suggests this was once a working community of some coherence. The surviving millstone fragments include a runner-stone piece, the upper rotating stone in a pair, with a raised band around its central perforation and rynd-bar sockets cut into the grinding surface. The rynd was an iron fitting that supported the runner-stone on the spindle; finding its sockets intact on a fragment like this is a small but concrete connection to the mechanics of the original installation. Local information indicates that a wooden shaft and other worked timber pieces were removed from the site in the relatively recent past, which narrows the physical evidence considerably but also confirms that organic material survived long enough to be retrieved.