A ideal cut diamonds which has no apparent colour is termed colourless. The colourless loose diamonds transforms the light which enters it and acts as a prism, dividing light into a rainbow of colours known as the ‘fire’ of the diamond.
The skill and accuracy of the diamonds cutter is crucial in bringing out the beauty and "fire" from the stones.
loose diamond is made up of carbon that was buried deep within the Earth under intense pressure and heat. It was made popular because loose diamonds is the hardest known substance.