GOLD BUSTERS - Key Persons
Rose gold is made when you mix gold with copper since copper has a reddish color naturally, (gold and copper are the only colored metals, all the rest are silverish in color). Rose gold may also vary quite a lot in color depending on the amount of copper mixed with the gold, the higher the copper content the more reddish the color.
White gold is an alloy of gold and at least one white metal mixed in, usually nickel or palladium. White gold's properties can vary dramatically depending on the metals and proportions used in the mix. This is done deliberately for different purposes for example, mixing gold with nickel makes it harder which is perfect for rings and brooch pins, while if you mix gold with a soft metal such as palladium then it becomes good for gemstones settings where a pliable gold alloy is required.