I say, and with God's success: If the vessel is made of pure gold, meaning that the percentage of gold in it is (100)%, then the zakat is on the full weight. If the percentage of gold in it is (60)%, then the zakat is also on the full weight, because the majority is treated as the whole. If the percentage of gold in it is (40)%, then the zakat is on the amount of gold in it only, which is (400) grams, due to the possibility of its purity, and this is more than the legal threshold. As for if the percentage of gold in it is (5)%, if there are only these fifty grams, then it is not subject to zakat, because it has not reached the threshold. However, if he has other money in addition to the fifty grams such that it reaches the threshold with these fifty, then zakat is due on this money. And if the gold is overpowered, meaning it is less than (50)%, if the vessel is offered for sale, then the zakat is on its total value at which it is sold in the market and is not specific to the gold present inside it, and God knows best.