Platinum is a naturally occuring white metal. White gold is created by alloying the naturally occuring yellow gold with metals such as nickel, copper, silver and zincto get a white hue. In addition, white gold pieces are often covered with a thin plating of rhodium (one of the platinum group metals) to strengthen them and give them a whiter appearance. Both only bear the aesthetic resemblance but differ in their composition, density, hardness etc.
Platinum is a chemical element with the atomic symbol Pt and an atomic number of 78. White gold is an alloy of Gold and has the same symbol as gold Au.
Platinum is a natural white metal while white gold is artificially given its color by alloying yellow gold with some metals and by adding rhodium plating to it. Platinum has the most luminescent white hue of all metals used for jewelry.
White gold has the same properties as yellow gold - meaning that 18-karat white gold is 75% gold mixed with 25% other metals. It is highly reflective and is not subject to tarnish. Platinum is also highly reflective and is 60% denser than gold. Platinum is purer than white gold. Measured in parts per thousand, platinum jewelry is typically 850-999 parts pure platinum (85%-99.9%), with the remainder made up of other metals. White gold isn't as pure or durable. Platinum is denser, heavier and stronger than white gold. Platinum is heavier (specific gravity: 21.4) than gold (specific gravity: 19.3). Platinum is 60% more dense than Gold.
Platinum is rare. Ten tons of platinum ore is required to process a single ounce of pure platinum. White gold isn't rare as its base, yellow gold isn't very rare. Platinum is said to be 35 times rarer than gold. This is also one reason which makes White gold cheaper than Platinum. Platinum is almost 3 times the rate of White gold.
All precious metals can scratch, and platinum is no exception. However, the scratch on platinum is merely a displacement of the metal and none of its volume is lost. Over time platinum develops a natural patina, which many people find just as attractive as a polished finish. Platinum does not micro-scratch the same as Gold, but actually “furrows” instead. On the other hand, when Gold is micro-scratched, the Gold metal is actually removed. Sometimes these micro scratches can leave white gold looking a bit yellowish
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In order to obtain pure platinum, the ore is crushed, made into a slurry, and then mixed with a detergent containing 'collector' molecules. Air is then blown through the mixture, enabling the grains of metal minerals to be separated from the rest of the mixture. This process is called "flotation" or "mineral beneficialness". The next step is smelting. White gold is made by alloying yellow gold with metals like nickel, palladium etc in different proportions.
Platinum is used in jewellery, laboratory equipment, electrical contacts, dentistry, and automobile emissions control devices. White gold alloys can be used for different purposes; while a gold-nickel alloy is hard, strong and therefore good for rings and pins, white gold-palladium alloys are soft, pliable and good for white gold gemstone settings.
Platinum is a better quality metal than gold. White gold, since made from gold, has a chance of wearing off it's white hue and hence isn't of the best quality in this context. The highest quality white gold is usually at least 17 karat, and made up of gold and palladium, sometimes with trace levels of platinum for weight and durability.
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Prices for White God and Platinum is constantly changing. Current prices for jewelry made of these metals are available on Amazon.com: