edit on 3-6-2014 by Blackmarketeer because: (no reason given)



I think of all the theories proposed, the wax seal embosser fits best. The "knobs" would act as stand-offs, allowing the seal to be pressed to a specific depth. Each face contains a unique design depending on where a letter may be destined or to whom it's sent. The holes may have contained a hardened wax design that would be changed time to time (to prevent forgeries). That could explain the wax residue in some of the artifacts. When it's time to change a seal, heat the dodecahedron, and the old wax melts away. Refill it and carve your new design and your back in business. (Hardened wax can still emboss soft molten wax.)Alternatively, the holes may have been left open so that once the dodecahedron was pressed into molten wax, it left the center un-embossed, where the signor could then press his signet ring to assure the recipient of who sent it. In a rank and file Roman province, there would have been different levels of importance of those sending letters (Generals, Consuls, Governor, etc.), so that might explain why the need for different designs in the faces of the artifact.Another factor in the mystery of these objects is that they are found in mainly European locations held by Rome. The use of letters and couriers sealed by wax may have been the reason why.Edit to add:Another reason for the variations in designs on the 12 sides might be to give the embossed seals a "progression", a crude enigma-like encoding. Each subsequent letter would use the next design in embossing only the sender and receiver would be privy to, say for instance, the next smaller seal impression on the dodecahedron. This way, if a letter is intercepted by an enemy, they would only be able to copy the seal design they have in front of them. They wouldn't know the seals vary and thus they'd inadvertently reveal the letter was compromised.