Yellow gold melts easily with no appreciable losses but you can always throw in a penny to add zinc and lower the melting point a few degrees. Also melt in a clay-graphite crucible rather than a carbon steel or even silicon-carbide since the clay graphite will not react with yellow gold and generally has a smoother finish that the other types. Some gold with adhere to the crucible walls and form a skin of gold foil but if you melt 8.0 ounces when including the remains in the crucible you should end with 8.0 ounces. White gold is harder to work with so avoid it. Actually the whole idea of doing this for anything except fun is probably best avoided as well. Goldbugs are strange people.
John Thornton