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The Clinker Stone House is eligible for the National Register of Historic Places under Criterion C for architecture. The house was built around 1940 by Charles Wynkoop, the owner of the ranch at that time. The stone used in the construction, clinker stone, is a natural phenomenon that only occurs in a few locations in the contiguous United States. The Powder River Basin contains the largest distribution of the stone, extending north into Montana and east into the southwest corner of North Dakota and the northwest corner of South Dakota. The stone forms when subterranean coal beds burn, baking the surrounding rock into an erosion resistant, porcelain-like material. Although anecdotal evidence suggests that ranchers in Campbell County used clinker stone to build fencing and outbuildings such as sheds and chicken coops, it is not known to be a common residential building material. The stone is mostly used in Campbell County and surrounding states as crushed aggregate for road beds, lending gravel roads in the region their characteristic red color, and as rubble stone for fence construction. The Clinker Stone House represents a unique construction type of hyperlocal materials and demonstrates the tenacity and creativity of Campbell County ranchers in sourcing construction materials during the Great Depression.