Would be interesting to use black and white rice, then convince your phone to read it as a QR code. That'd vastly simplify the before/after comparison.
> An alternative to sealing is embedding the whole object in a substance whose surface forms a mosaic that is difficult to reproduce and changes when manipulated.
The problem with a QR code is the “difficult to reproduce” part —- if you can organize the rice in such a way that it’s recognized as a valid QR code, surely the attacker can recreate the same QR code (or an equivalent, since QR codes have redundancy/ECC).
