Why Diamond is colorless?

Question

Heat and high pressure changes carbon to a colourless transparent stone. What is the chemistry behind this change of colour?

Answer 1

light reflection

Answer 2

Eugene N and jim z have the only correct responses to this question.
Many different types of crystals would be colorless if they were pure. This includes, diamond, quartz, rubies and sapphires (mineral name: corundum), emeralds, cubic zirconia, topaz, and many others...
Color in minerals has to do with electronic transitions that occur in the crystal structure. If these transitions occur at the same energy level as incident light, then that light gets absorbed. Colorless minerals simply do not absorb any visible light and appear transparent. Elemental impurities and defects in the crystal structure cause some visible light wavelengths to be absorbed and thus impart color.
Pure diamonds are colorless because they consist of 100% covalently bonded carbon atoms, and these little guys just don’t absorb any visible light. Yellow diamonds are yellow due to nitrogen impurities. Sapphires are blue due to titanium and iron impurities. Rubies are red due to chromium impurities.

Answer 3

Something is Transparent because light can get through it without being effected by it. This is generally true if the interatomic (or molecular )distances are large enough and the lattice is perfect enough that the light can get all the way through with out hitting an atom (or molecule). Diamonds are pure carbon and the pressure make for a perfect and wide open lattice. Light can be effected though. That is why you get yellow or blue diamonds.

Answer 4

Pure diamonds are colorless if they are perfect crystals. A diamond will allow light to pass through but it dramatically slows the light. This slowing results in the high degree of refraction or bending of the light as it passes through. This is why it sparkles so much. Sometimes impurities will cause certain colors. Noone seems to know what causes the color red in some highly prized diamonds.

Answer 5

It's not chemistry. It's physics. The carbon atoms are arranged in a lattice which just happens to allow light to pass through. Glass does something similar. If they actually understood the process, transparent iron and aluminum would also be possible.

Answer 6

There is something in all crystals called the band gap energy. It's how much energy is needed to move an electron from being bound to the atoms into the conduction band. The band gap is so high in diamonds because of their crystal structure that visible light energy is lower than the band gap and cannot be absorbed. It passes right through.

Answer 7

Diamonds are extremely refined/ cut/polished gem that carbon is processed in such a way that it appears clear. With this procedure diamonds acts as prisms that cuts a light and spread it to a color spectrum which we all know... Because of this thorough procedures diamonds attain it's unique quality of being colorless ^^,

Answer 8

While others have given excellent answers to this question you should note that not all diamonds are colorless. It is possible to find naturally occuring colored diamonds.

Answer 9

poets doesn't know the chemistry or physicis......we only know the language of love which the diamond reflects......diamond has dual action they are colorless but reflects colors like feelings.....they are precious like oxygen that is also colour less they are important like soul that is also colour less ...they are beautifull like fragrance which is also colourlesss...every thing that has the most special color of life is colorless like diamond.