Well I didn't mean in bank safe deposit boxes. In the 1930s they got locked down by FDR, and I bet they get reported to the IRS, Homeland Security, and maybe the local organised crime guys if you deposit enough gold/gems there. I mean your own safe buried out in the woods/desert/mountains.
I don't know that much about it. IMO the main reason to do it is lawsuits. I am confident of my ability to identify at-risk banks/brokers etc before they go bust, ditto with currency devaluations, revolutions, wars and so on. If I was in the USA I would own about 5-10% in gold abroad just in case I got sued into bankruptcy because a drunk pedestrian ran out in front of my car, or I spilled coffee on someone etc. If I was worth big money then I would do it for sure. Barton Biggs wrote a book talking about preserving wealth during wars, revolutions etc, I found it useful. The conclusion was that a rural farm is the safest wealth preservation during wartime - residential/farmland in the countryside is the last thing to get confiscated. Along with maybe gemstones (portable, easy to hide) it's probably the most safe option, but comes at some cost in hassle as well as $$$ to own (no dividends/interest). Gold is too conspicuous and heavy, and if it's in a bank vault then it's not secret, and in social chaos/war you sell it for like a 75% discount to some middleman. An ex of mine used to live in Tanzania and her family lost a fortune trying to get gold out of the country - the govt imposed capital controls and body-searched everyone for gold, diamonds etc at the borders, they got caught and it was all stolen and they were lucky to avoid jail. Being smart you could smuggle it out bit by bit, but its still risky. IMO a far better hedge is just keep things abroad. If you own stock in certificate form in at least 3 continents, then only really WWIII or global communist/Taliban takeover is going to screw you, and in that case you are either going to be fighting in the resistance or living a life of misery regardless of any financial planning. I would say just keep 30% of assets in other G7 countries, and if gold gets banned then buy some physical platinum in Switzerland/Canada etc. I guess maybe $50k in gold or gems hidden in an underground safe is worth it. The land will only cost a few thousand. If I was less lazy I"d do it myself. There's also the cool factor of the world social & financial fabric falling to pieces, all your friends & family are broke, starving, and in panic, and you strut up and say "Ok bitches, time to go get my stash", then you crack open an underground safe with guns, ammo, gold bars, diamonds, 100 days worth of canned food, and genuine tin foil hat
If you are going to hide something overseas might as well hide you gold or gems in the ground on your farmland especially if you don't trust banks. Pretty damn hard to find. Didn't UBS advise their clients to smuggle their diamonds out via toothpaste? Another idea I had heard of was to hide your money in multiple safes at your home the first conspicuous, the following built in to the structure and drywalled over never to be open except in emergency.