Another of those fun pop-up articles.
I'm leaning towards the masterwork explanation - because I own an 6 sided solid machined metal cylinder, which was an apprentice test piece. It had to be fitted inside a six sided hole in another metal cylinder - both ways up so 12 variations - and the fit was tested with measuring shim. The apprentice lost 1 mark for every thousandth of an inch they were out.
The Mysterious Bronze Objects that Have Baffled Archaeologists for Centuries
The first dodecahedron was discovered nearly 300 years ago, yet no one is certain just what they were used for.
getpocket.com
I'm leaning towards the masterwork explanation - because I own an 6 sided solid machined metal cylinder, which was an apprentice test piece. It had to be fitted inside a six sided hole in another metal cylinder - both ways up so 12 variations - and the fit was tested with measuring shim. The apprentice lost 1 mark for every thousandth of an inch they were out.