Finding Portable Rock Art (PRA) is fascinating to me because I never know what I will find next. A walking trail along the Deep River in North Carolina has a lot of PRA. Sometimes I go there with a backpack and squirrel away anything that looks like prehistoric art. Back at home, I'll pull out my findings to decide on what I may keep. Bear in mind it's a lot harder to find an arrowhead than to find PRA.
You could find a sculpted or indentured rock, be it Quartz, Garnet, Schist, or Flint, some still have paintings, and some are just drawings. Some have holes bored out to resemble a cave or hideout. Some have what they call Faces in Faces where you make out a face, blink, then it looks like a different face.
Next time you're on a nature trail start looking down at the rocks on the ground. Some rocks with art may be bigger than your fist, and others are small where they are held between your index finger and thumb. Zoom in on the featured image to get a better idea of what to look for.
Look for familiar shapes. If you see what looks like a set of eyes then look down to find a nose. Some paintings or drawings are of people, others are pre-historic animals or fantasy creatures. Ancient man and women used their imaginations to I've found.
Slowly twist the rock clockwise and you'll start discovering sculptures, carvings, and paintings you didn't see before. Adjust the light from full sunlight to 20% sunlight. Some PRA reveal images, carvings, or sculptures better in full light, others in the shade.
I hope this blog post inspires you to search and find a masterpiece.