White Gold
Being a frigid color, white or grey gold is most modern. It magnifies the diamond pavings and enhances the solitaires with an elegant tone. White gold is much more resistant and does not oxidize unlike silver. Nonetheless, it is possible that white gold turns slightly yellow after normal wear, which is completely normal. A simple coat of white rhodium every 3 to 5 years is sufficient to give back its original luster. 18-carat white gold is composed of 75% gold, 24% silver and copper. Its 9-carat equivalent is composed of 37.5% fine gold and 62.5% silver. A layer of white rhodium is applied to give them both a pure white color.
Yellow Gold
Yellow gold is a warm color that embodies classic jewelry. It embodies the precious nature of this rare metal. It is the only yellow metal that does not oxidize and will forever stay the same. 18-carat yellow gold is composed of 75% pure gold, 12.5% silver and 12.5% copper, in order to obtain the best compromise between color and mechanical properties. The 9-carat version is composed of 37.5% fine gold, 12.1% silver, 44.4% copper and zinc.
Rose Gold
Rose-colored gold has a fair-skinned carnation-like color which is very soft, less frigid than white gold but more modern than yellow gold. On dark skin, it stands out magnificently with an original touch. 18-carat rose gold is composed of 75% gold, 5% silver and 20% copper which gives it its color while 9-carat rose gold is composed of 37.5% fine gold, 42.5% copper and 20% silver.
To know more about 9 or 18 carat gold 
