Picture of a Lerma Rounde Base blade - 126 mm - 192-89-C

Point Type: LERMA ROUNDED BASE
Also See: Agate Basin , Allen, Angostura, Eden, Guilford, Lerma Pointed Base, Nebo Hill,
Sedalia

Location: United States, Canada, Mexico, South America

Associated Dates: 10,000 - 5,000 B.P. - Transitional Paleo - Early Archaic
Morphology: Lanceolate

General Description: The Lerma Rounded Base is a medium to large sized long, ovoid, likely to be leaf-shaped form,  having excurvate sides and a rounded basal end.  Some points have small serrations on the blade edges.  The stem end contracts to a rounded shape.   The stem is usually lightly ground.

The longer and broader examples of the type are thought to have doubled as knives or spear points.  The blades are thickest in the middle and then are thinned down to the edges.  Some examples were turned into drills through material conservation. 

The type was manufactured by applying Transitional Paleo flaking technique, irregular pressure and percussion flaking .  Alternate biface bevel flaking or alternate uniface bevel flaking was used in finishing the blade edges.  The cross section is rhomboid, lenticular with one beveled face, or lenticular.

The average example measured 109 mm long and 28 mm wide as the bade base junction which is the widest dimension and averages 9 mm thick.

The Lerma Rounded Base type apparently lasted over a long period of time.  Suhm and Krieger (1954) suggest that it appeared earliest in southern Tamaulipas Mexico several thousand years before the Christian era.   The late Paleo to Transitional Paleo affiliation for this tool is substantiated by its associations in surface collections with the Beaver Lake and the Greenbrier Dalton point types.  In one case, a Lerma Rounded Base and a large Beaver Lake point were recovered from a stratified pit in close association. 

The point is found in Texas in the Edwards Plateau Aspect and the Pecos River Focus and the Aransas Focus, all representing the Archaic Period.  The point is found from Alaska through Canada and down into Mexico, South America and all across the United States.

The Lerma Rounded point type  was named by Richard S. MacNeish for examples that were recovered from the Canyon Diablo site of Tamaulipas, Mexico and described by Dee Ann Suhm, Alex D. Krieger and Edward B. Jelks in 1954 in the Bulletin of  The Texas Archeological Society # 25 

About the Point Above: The large Lerma Rounded Base knife form pictured at the top of this page, was found in Humphreys County, Tennessee in 1920's and is from the former Frank Morast collection. The point still retains the Morast label which states "Found Stone Blade Humphreys Cnty, 60x 205?" The point appears to be made from a very dull tan brown Dover chert and is very heavily patinated, especially along the blade edges. The base edges and blade surfaces are ground and smoothed. The side of the blade with the label has been bifacially beveled for resharpening purposes.   The edges are ground 29 mm up each blade edge from the base. The cross section is lenticular. Overall, the point measures 126 mm in length, is 23 mm wide and is 9 mm thick in mid blade 54 mm from the base. Most of the blade is only 4.6 mm thick.  Catalog Number 5-80-H

References: Baker, Bell (1), Dragoo (4),  Overstreet

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