Mythbusters did it:

> Adam and Jamie first visited the zoo to obtain a variety of feces to try to polish. Poop collected, they tried to pick the most polishable candidates, and then baked them to remove the moisture. Adam tried to shine his poop with a buffing wheel, while Jamie's tactic of applying a furniture polish caused a philosophical disagreement between the two. Adam eventually brought in an outside expert to teach them dorodango, a Japanese art form that allows a practitioner to apply a shine to dirt using nothing but water and physical effort. Applying this technique, Adam and Jamie were both able to polish balls of poop without using any foreign materials as judged by a gloss meter, exceeding a standard of 70 gloss units for high gloss.[0]

[0] - https://en.wikipedia.org/wiki/MythBusters_(2008_season)#Epis... (Section: You Can't Polish Poop)