How Are Coloured Diamonds Made?

Yellow diamonds get their colour from nitrogen molecules that absorb blue light, making the diamond appear yellow. These are relatively common compared to other coloured diamonds.

Blue diamonds contain boron, which not only gives them their colour but also conducts electricity. The famous Hope Diamond is an example of a blue diamond.

Green diamonds are exceptionally rare and their colour is typically caused by exposure to natural radiation over extensive periods. This radiation displaces carbon atoms, affecting the diamond's ability to absorb certain light frequencies and thus imparting a green hue. Additionally, trace amounts of nitrogen can also contribute to the green colour in some diamonds.

Pink diamonds are among the rarest. The cause of the pink colour in diamonds is still a topic of debate among gemologists. A leading theory suggests that the pink hue results from distortions in the diamond’s crystal lattice. This structural change is thought to occur due to intense pressure during the diamond’s formation, altering how light passes through and is perceived as pink.

Brown diamonds are the most common coloured diamonds. They get their colour from lattice defects in their structure. These defects are thought to be caused by internal graining, which affects how light is absorbed and reflected.

Black diamonds, or carbonados, are tough and porous types of natural diamonds. They are thought to be the result of supernovae explosions and are found only in Brazil and the Central African Republic. Their colour comes from dark inclusions and graphite.