First of all, I feel gold is undervalued (or cheap) due to price manipulation. So it's a value. Second, The petrodollar causes roadblocks for countries that don't want to deal with the US. If the USD is backed by nothing more than a trust that the US military will put a foot in your rear if you don't fall in line, and it's the only currency one can use to buy oil, a gold backed alternative to buy oil would sound very inciting. In conclusion, Russia and China are ready to offer an alternative to the petrodollar with a gold backed currency.