Many, many, many years ago, when we were out West and in various deserts, I picked up odd pebbles here and there that had a unique appearance (to me!) I was told they were 'eroded' by windblown sand, which gave them a light sheen, but kept a more organic texture to the stones--like the ones in your pictures. I'm used to pebbles eroded by water, which have a more uniform look.
I'm gonna go look for some right now! :^)
Luann Udell
artist & writer
Ancient stories retold in modern artifacts
LuannUdell.com