Silver + Gold stacking while cruising?

[Ivory]

Apparently over 10k in money you have to declare in many countries. But what about hidden gold or silver you are saving on your boat? Or jewels and jewelry making supplies (so gold wire and things like that).

Of course I don't plan on having hundreds of thousands on the boat, but 20-40k in gold and silver seems reasonable for emergency economic situations to me and material to work with.

Especially given the current global economic situation (which doesn't seem great to me)

Anyhow, any thoughts? Hiding it doesn't seem like it would be much of a problem with a few nice hidden compartment objects or tables / boxes.