Designed by my daughter, who has allowed me to upload it as some of you may also like it :)  Printed with no fill, no floor and no roof with 2 shells/perimeters.  I printed this in natural PLA at 0.3 mm layer height, and it took 3 hours to print.  I used http://3dp.rocks/lithophane to convert the image and merged/unioned it with a cylinder for a shell only print.Update:I've changed the lithophane generator so that you can produce these STL files directly from the image file without any post processing. Just select '360 solid shell' under 'Form:'