[jschulenklopper]

I'd think that a block of resin would be equally suspicious, warranting an inspection immediately, but IANACBPO.

Otherwise, a block of (say) white icing sugar, encapsulated in a block of (opaque) resin, would pass a machine inspection and icing sugar-sniffing dogs at the border... and a lot of icing sugar would enter the country in a resin mold.