Original source: https://www.thingiverse.com/thing:1012118

I printed Imirnman's stones a year or so ago and then ran out of matching filament. Well I got around to getting more and found that they had updated their files. I ran into problems with the Earth stone (I haven't looked at the others) because the inside wall is too thin to slice properly with my 0.5mm nozzle. The grooves end up becoming holes about half way through (see picture). I probably could have forced a single wall print, but I didn't want it to be that thin.

I added approximately 0.8mm is thickness to the inner wall by shifting the face in Meshmixer inward, and then used Netfabb to fix the holes created by the self-intersecting faces.

I used supports for the grooves, but not for all the cracks. I printed it upside down so that I didn't have to fill the entire inside with supports to print the top. Came out well and the walls are intact.