Consists of light-colored either coarse-grained or micritic limestone, informally divided into lower and upper members. Thickness ranges from as much as 415 m at type section to 0 m (Brosgé and others, 1962). Also includes oolitic and glauconitic limestone; weathers light-gray and cream colored (Reiser and others, 1971). Unit is uppermost part of the Lisburne Group in eastern Alaska and likely extends into the Yukon where the Lisburne Group adjacent to the Alaska-Yukon border is mapped as an undivided unit; elsewhere in the Yukon, equivalent rocks are mapped as the Ettrain Formation. A Late Mississippian age was reported by Armstrong and Mamet (1977), whereas Dutro (1987) suggested age was Pennsylvanian only