HARL
Harl
In Scottish usage, harling describes an exterior building-surfacing technique which results in a long-lasting weatherproof shield for a stone building. A pigment can be embedded in the harled material, thus obviating the need for repainting. Harling as a technique provides the surface of many Scottish castles, but it is also used for a variety of common everyday building types. Long-lasting and practical, it well suits structures in the Scottish climate.The above text is a snippet from Wikipedia: Harl
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