Mapped in southwest part of quad, 4-6 km south of town of Round Mountain, Nye Co, NV, Great Basin province. Divided into quartzite, limestone, and argillite units which are separately mapped; limestone and argillite units are further subdivided into separately mapped units. Units are shown in correlation diagram in their approximate stratigraphic sequence based on evidence in Manhattan quad to south of Round Mountain quad and in Toiyabe Range to west (F. G. Poole, 1992, oral commun.). However extreme deformation in Round Mountain quad has resulted in some lithologic units being juxtaposed out of stratigraphic position. Original thickness uncertain because of deformation; probably several hundred meters thick. Correlates with part of Palmetto Formation of southern NV. Toquima represents youngest Paleozoic rocks in study area; in thrust fault contact with underlying Zanzibar Formation. Graptolites (list provided) are preserved where argillite units are in contact with quartzite; graptolites also occur within some of subordinate argillite interbedded with quartzite unit. Graptolites identified by R. J. Ross, Jr. (1974, written commun.) indicate Mohawkian (Middle Ordovician) age.

Source: GNU records (USGS DDS-6; Denver GNULEX).