"I contemplated the notion of Flow (Mihaly Csikszentmihalyi) and the states of consciousness that may have been experienced during the intimate carving of the rock; the performative nature of this, the rhythm and the repetition the ‘artist’ may have engaged in and the very act of striking on the rock could fracture the crystals within the tool to cause triboluminescence, thus emitting light. "
You would have had to use quartz to get the triboluminescence and you wouldn't see it noticed unless you did it the dark , is it likely that outdoor rock art was engarved in the dark ? What was missed from the performance , if quartz was used as the means of percussion , is the smell . Quite distinctive ,and present day or or night .
Nothing wrong with getting varied opinions from all sorts .
But it's a bit sad that nobody knew to point out the obvious to Angela .
At least we can do her the favour and point her in the right direction .
Let it Be ...? "And when the night is cloudy
There is still a light that shines on me "
But not triboluminescence during the day and it's not that great at night either .