The Lake Manix Lithic Industry
Surface sites of the Lake Manix Lithic Industry have been recorded in the northern half of the Manix Basin (Simpson 1960, 1976; Alsoszatai-Petheo 1975, Binning et al. 1985). They are devoid of pottery, shell objects, and projectile points. Lithic artifacts, fashioned primarily of chalcedony, chert, and jasper, include large oval bifaces, scrapers of several forms (end, straight, concave, pointed, convex, pointed, and plano-convex), cutting tools, choppers, chopping tools, large stout picks, gravers, cutting tools, rotational tools, and flakes, as well as cores, anvils and hammerstones.
Manix Lithic Industry artifacts are often found incorporated into desert pavements, and usually exhibit rock varnish on both their buried and exposed surfaces: sporadic black, manganese-rich varnish atop orange, iron-rich varnish on exposed surfaces, and orange, iron-rich varnish on surfaces in contact with the soil. Younger Paleo-Indian artifacts found at lower elevations along the river and in sand dune sites are not varnished, nor are they incorporated into desert pavements.
Based on a dated pollen profile at site CA-SBR-2120 and the occurrence of this assemblage above the most recent shoreline elevation of Pleistocene Lake Manix (543 m), the Lake Manix Lithic Industry is inferred to be at least 18,000 years old.
The presumed eastern extension of the Yermo Fan, known as The East Rim Site (CA-SBR-2120), is a lithic workshop with bifacial and unifacial artifacts as well as debitage on and beneath a desert pavement surface to a depth of 15 cm (Alsoszatai-Petheo 1975). Recovered pinyon and juniper pollen suggests occupation 17,000 – 34,000 years ago. Unifacial artifacts include choppers and end, side, and convex-edged side scrapers. Bifacial artifacts include chopping tools, generalized bifaces, wedge-shaped bifaces, ovate bifaces, cutting tools, and utilized flakes. Unflaked artifacts include hammerstones, pecking stones, and pointed tools. Rare specimens include multiple scrapers, tortoise scrapers, gravers, pointed scrapers (borers), and keeled scrapers.