Key for Notched Points

Notched points have pronounced shoulders with Shoulder Angles greater than 100º (although some Small Corner-notched points may measure a few degrees below this threshold). In general, "notches" are as deep as or deeper than they are wide which distinguishes them from "corner-removed" stemmed points discussed in the following section. The notches produce a distinct neck which clearly separates the base portion of the point from the blade portion. Shoulder Angle is a useful measurement for larger points (Blade Width greater than 16.5 mm) but does not consistently separate some of the smaller point types.

Follow the steps below to accurately classify notched points.

Step: Go to:

  1. Blade Width
    1. Greater than 16.5 mm - Step 2
    2. Less than 16.5 mm - Step 3
  2. Blade/Base Ratio or Shoulder Angle
    1. Blade/Base Ratio greater than 1.125 or Shoulder Angle less than 142.5º - Elko Corner-notch
    2. Blade/Base Ratio less than 1.125 or Shoulder Angle greater than 142.5º - Northern Side-notch
  3. Blade/Base Ratio
    1. Greater than 1.125 - Rosespring Corner-notch
    2. less than 1.125 - Step 4
  4. Base
    1. Has central basal notched - Desert Tri-notch
    2. Does not have central basal notch - Step 5
  5. Neck/Base Ratio
    1. Greater than 0.575 - Avonlea Side-notch
    2. Less than 0.575 - Desert Side-notch
All content Copyright © 2009 by Richard N. Holmer
Informatics Research Institute