Initial mineral exploration in the area surrounding Round Top commenced in 1969 and continued through the late 1970s. Work in the area included prospecting trenches as well as approximately 22 drill holes within fluorite outcrops in the area. Although a downturn in the fluorite market inhibited further project development, this early work led to the identification of beryllium mineralization in the area. During the 1980s, Cabot Corporation conducted further beryllium exploration at Round Top consisting of mapping, sampling, and reverse circulation rotary drilling. In 1987, Cabot entered into a joint venture agreement with Cyprus Metals Company to continue beryllium exploration focused on Round Top resulting in a feasibility study completed in 1988. Ultimately, Cyprus decided to exit the beryllium business and chose to refocus its efforts on copper mining, eventually merging with Phelps Dodge in 1999. Throughout the 1990s, the Round Top project lay dormant, eventually falling back under control of the Texas General Land Office. The project was subsequently acquired by Standard Silver Corporation, which changed its name to Texas Rare Earth Resources Corp. (TRER) in September 2010 to more appropriately reflect the current focus on Heavy Rare Earth Elements (HREEs).