Yuma
From a somewhat later period we have evidence of ancient hunters who made some of the most beautifully flaked stone projectile points that have ever been created. These points, which were first found in Yuma County, Colorado, are known as Yuma or Parallel Flaked Points. They are of two types.[130] One is marked by the removal of long narrow spalls running obliquely across the blade and the other is characterized by the removal of shell-shaped spalls from either side which tends to give the point a diamond shaped cross-section.