Rose gold is a gold and copper alloy widely used for specialized jewelry due to its reddish colour. It is also known as pink gold and red gold. Because it was popular in Russia at the beginning of the nineteenth century it is also known as Russian gold, although this term has become somewhat rare. Since it is an alloy, there is no such thing as "pure rose gold"; pure gold is yellow and pure copper is reddish. Although the names are often used interchangeably, the difference between red, rose, and pink gold is the copper content: The higher the copper content, the stronger the red coloration. A common alloy for rose gold is three-quarters gold and one-quarter copper (18K). That is to say 75% gold and 25% copper and the other alloies.
Many jewellery companies say they can make the rose gold no any discoloration or disrupture. Actually,it can't be ture. Copper oxidates easily. Therefore, rose gold will be darker after a long time you bought. It can be shiny again after polishing,but it still takes time.
However, there're still a lot of peoples love this metal very much, disregarding it's disadvantages. They're crazy for the fancy color. Moreover, when they put rose gold jewellry on, they can't help liking the fiber it has.
Finally, pay attention to the difference between Rose Gold and Plating Rose Gold(Fake Rose Gold). Plating Rose Gold consists of a very thin plating of copper over a layer of silver. No actual gold is used. When time goes on, it will turns to white or black,because the main part is silver or the other alloy. For actual rose gold, after a long time it will be darker than that when you bought, but it won't turn into any other colors.Because it consists the same material---Rose Gold.