Platinum
The jewels in platinum are generally pure to 95%. To comparison the gold to 18 carats is pure to 75%. No metal in jewelry shop is completely pure and all have one alloy, that is one mixture of other metals. The platinum has little alloys, for this it is therefore pure that does not change to aspect or color and maintains the own brilliance for years. Pure and the white woman brightness of platinum reflects in ideal way the beauty of the diamonds, assures the better estate for precious stones and is a perfect complement to the yellow gold. The purity of platinum is moreover ideal for the skin because, on the contrary of some present alloys in other metals, not cause some allergic reaction.
Rare
The platinum is 30 times rarer of the gold and it finds in least giacimenti the world, above all in South Africa and Russia and, in amount many minors in Zimbabwe, Canada and South America. Every year approximately 90 tons of platinum they come transformed in jewels, to comparison of the 2,700 tons of gold. 8 weeks and 10 tons of cliff are necessary in order to produce to a single ounce (31.1 grams) of platinum, while five tons are extracted alone in order to obtain the same amount of gold. Moreover the platinum mines are much less numerous. The relationship with the gold mines is of 10 to 1. One platinum nugget pure.
Eternal
The density and the specific weight of platinum render it more long-lasting than other metals. A hung cube of 15 cm of platinum 75 Kg, more or less the weight than one person. The platinum is moreover resistant to the heat and acids and has a melting point much elevating: 1.768°C. The platinum is not consumed and offers advanced guarantees of emergency for the incastonatura of precious stones. Some of the more precious gems of the world are incastonate in platinum, like the famous Koh-i-Noor diamond, than ago part of the jewels of the English Crown. All the precious metals are marked and the platinum does not make exception. However, while the gold is marked for dispersion and with the time its volume is consumed and reduced partially, the platinum is marked for jam and it does not lose weight absolutely. When they appear of the obvious signs on a platinum surface, jewelers qualified it can supply to the polishing.
Poured
Beyond to the resistance and the density, the platinum has an other considerable characteristic - the ductility. The platinum is therefore ductile that with a gram of metal can be produced to a thread along nearly 2 km. This quality, exacta to its hardness, has allowed the gioiellieri to use platinum in order to create of pieces and the extraordinary workings that could not have been realized with other precious metals. The platinum moreover is used in many other fields: in the industry for the fabrication of catalytic stock-pots and in medicine for its anallergeniche qualities. The platinum in fact intaccato from the reaction oxidant of the blood, has an excellent conductivity and is compatible with the living woven one. For these its property is used in the pacemakers. Currently more than 50 mila persons all over the world thanks to the pacemakers and platinum live.