HOLE WALL SURFACES:
Modern rock holes have different characteristics than Ancient holes that allows us to tell them apart.
A portion of Peacemaker Rock was drilled, blasted and quarried around 1960.
1. Ancient hole surfaces are often (always?) vitrified. This includes the Small Holes.
2. The star holes have protruding lobes. There are even a few tubular holes that have mineral protrusions.
3. Ancient holes often have artificial mineral coatings inside of them.
4. Ancient hole walls are textured.
PROTRUSTIONS ON WALLS:
Some holes have protrusions extending from the hole wall.