Subject title is bullshit. India did not outlaw gold. As always was the case, gold can be purchased with after-tax money.
The new thing is that the gov is now demanding that all gold be shown to be purchased with after-tax money. And, apparently, resorting to draconian measures to determine if each person's gold above some threshold has been purchased accordingly.
But it has not made gold illegal.
This sounds like Civil forfeiture in the USA, but on a much larger scale.
Call it what you like, but if you have gold, you now have to prove that it is clean or you lose it. They are going to rob their citizens blind...