Are there restrictions on taking physical gold out of the US if I emigrate? Can I just pack it in my luggage and get on a plane to UK?
The airlines say not to put valuables in checked luggage. But both passengers and carry-on luggage are searched for metal. Obviously, the gold owner does not want the security gate personnel to be juggling their gold.
Also, if the gold were in carry-on baggage then every time someone was pulling something out of a bag, the gold owner would want to stand-up and watch their own bag. So the gold should be carried in a sling on the gold owner's body and under a coat.
A kilogram of gold is worth about $45,000. Suppose an investigator asked for an origin-of-funds ? And so paperwork on the gold is recommended.
If the gold is shipped as cargo then it can be insured. Then both the shipping company and the insurance company could have requirements.