It really should be clear that a major international banking crisis is inevitable, and likely to occur fairly soon. Due to the extreme debt levels, many banks are close to that point of failure.
An event like a stock market crash is likely to push many banks to that point of failure, since the pressure it would create (on cash resources), would expose their inability to fulfill their obligations.
Cash (not bank credits/digits) is still the means by which banks have to settle liabilities and obligations (especially amongst each other). If a bank goes down, it will be due to the lack of cash (not bank credits/digits). It is for this reason that there is a campaign to ban cash (for the general public) or limit the use of it.
The banks are in competition for the available cash resources, and they do not want you to be an obstacle. This is similar to what happened during the Great Depression (1933) when gold was confiscated. Then, banks proved their solvency with gold; therefore, the general public was prevented from competing for the limited amount of gold resources.
It is for this reason that I believe it is very unlikely that gold would be confiscated during this crisis. Today, it is cash that is the cornerstone of the banking system (especially the US dollar), since it is cash that is promised, not gold.