On the different hand 9 carat gold is only 37.5% gold and it contains different metals such as silver and copper that makes up the rest 62.5%. Thus, 9 carat looks a little lighter in shade and much less expensive.
Mixing exclusive metals with gold can give it different colorings and shades as well.
Rich yellow is the original color of gold. When mixed with white metals such as rhodium and titanium gold jewellery has a white gleam which is comparable to platinum. A mixture of gold and copper turns into pinkish hue that is known as rose gold. Traditionally, solely yellow gold and rose gold (Eastern Europe) was used but in current times white gold has become very popular.