What is the ruling on one who hands over his gold to a goldsmith to work it, and his gold may be mixed with the gold of others when the gold is melted, but when he takes it back from the goldsmith he gets the same weight of gold as that which he handed over?.
The goldsmith should not mix people’s gold together; he should keep it all separate if the standard of the gold varies.
But if there is no difference in the standard of the gold, then there is nothing wrong with putting them together because it does not do any harm.