Base metal-silver prospects have been known to exist in the upper Swift River region since 1946. These prospects, occurring in Yukon-Tanana terrane, have been previously described as isolated skarn occurrences and have hitherto received limited prospecting attention. Exploration work at the Mod property in 2016 has indicated that the sulphide mineralization is deformed (hence it predates the adjacent Cretaceous Seagull batholith) and that it demonstrates textures that are not consistent with a skarn origin. If, indeed, this mineralization is of exhalative origin then a large region of Yukon-Tanana terrane becomes prospective for mineralization similar to that of the Finlayson VMS district.