The Indian government is also confiscating gold taxing holdings of black money, which is making bitcoin more and more popular in India. Any gold that hasn't been taxed gets confiscated taxed if their government can find it.
FTFY
By "black money" do you mean money tainted by contact with our evil banking overlords?
Probably gold that's had no tax paid on it. If they have an inheritance tax in India I doubt anyone admits they inherited a shit load of gold to the government. They probably also use it to buy and sell things and don't bother declaring the transactions for tax.