At any rate, today I saw an older video of a woman painting mandala stones and I just couldn't seem to look away.
The artist, Australian Elspeth McLean, has a website, and she paints much more than mandala stones. Here's another example, but there is more on her site along with links to places where her work can be purchased.
Right now she's taking a break from painting mandala stones in her Etsy shop (back next month, I think), but a quick trip around Etsy turned up almost 2,000 results for mandala stones by other artists. The variety is interesting. Here's an example:
And if you'd like to paint your own mandala stones, here's a tutorial. Enjoy!