In general, one can say that gemstones are only fragments of minerals crystallized in a different way than usual. Its value is more due to their rarity that the preciousness of the materials that compose them. There are many kinds of precious stones but only four of them truly deserve this title diamond, emerald, sapphire and ruby \u200b\u200b.
The diamond is the hardest mineral found in nature. This feature, along with the beauty and rarity which is famous for, making it the most expensive stone.
In its raw state, this gemstone is not very appealing.
The ancients believed that colored stones possess some special powers to cure diseases. Because of its beautiful colors were used in majestic jewelry especially for kings and nobility. At present these gems are in high demand.
The ruby \u200b\u200b the emerald and sapphire are the only three colored stones considered precious, this is due to meet the three characteristics that make them very valuable, its hardness, shortages and extraordinary colors. Colored gemstones of good size and quality are so rare that one without a strong color imperfections may be worth the same or even more than a diamond of the same quality. 
