Platinum, iridium, osmium , and neptunium are the only metals with density higher than 20 grams/cm

Answered by sathish kuma , an ibibo Specialist, at 11:28 PM on January 13, 2009

For its beauty and value, platinum has always been the ultimate expression of celebrations of all kinds: from weddings and anniversaries to birthdays, holidays and other special occasions. One of the rarest precious metals on earth, platinum is found in only a few locations in the world. Platinum has a rich and noble history. It was first used by the ancient Egyptians about three thousand years ago. Eight hundred years later, the South American Incas worked with platinum. The first platinum jewelry in Europe appeared around the year 1780, at the court of Louis XVI of France. It may surprise you that, although platinum has been around for centuries, it has only been used to fashion jewelry for less than two centuries. It is both an ancient and a young metal.
Platinum is among the finest, purest and rarest precious metals on earth, and has an understated elegance that appeals to both men and women. Platinum is strong. Platinum, one of the strongest and most enduring metals in the world, is also one of the heaviest: it weighs 60% more than karat gold. It is ideal for jewelry worn every day because it exhibits little material loss, even after prolonged wear.
Platinum is pure. In the U.S., platinum jewelry generally contains 90% or 95% pure platinum. By comparison, 18 karat gold is 75% pure gold and 14 karat gold is 58% pure gold. Platinum is hypoallergenic and resists tarnish. Platinum is rare. To produce a single ounce of platinum, a total of 10 tons of ore must be mined. In comparison, only three tons of ore are required to produce one ounce of gold. Rarity lends platinum its cachet. Platinum is lustrous. Platinum's rich, white luster perfectly complements diamonds and other precious gems. Its neutral color enhances a stone's brilliance and depth. Platinum is fashionable. Platinum jewelry appeals to many people today because of its subtle beauty and elegant understatement. Many platinum jewelry designs are accented with 18 karat gold, creating a sophisticated, versatile and fashionable look.

Answered by Ajay Chawla , an ibibo Master, at 7:44 PM on January 09, 2009

well kunnu,

1. Before purchasing the gold, check the label, if it has one. On rings the stamp will be on the inside and on bracelets and necklaces it will be in the clasp.
2. If the label does not say 10k, 14k, 18k, or 22k, then it is probably not real gold.
3. Ask the person who is selling it about how many karats are in the piece of jewelry.
4. Test the density of gold. It is about 19.3 grams/cm cubed, which is much higher than most other metals. Platinum, iridium, osmium, and neptunium are the only metals with density higher than 20 grams/cm cubed. To test its density, use a scale and a graduated cylinder. First weigh the gold, and then put some water in the graduated cylinder. It doesn't matter how much, but keep note of the amount. Then put the gold inside the water (this won't damage it) and note the water level. Get the difference between the two numbers for the volume of the gold. Density= mass/volume. If the answer is close to 19 grams/cm cubed, then it is real gold.
5. If you do not care if there is a small dent in the gold, bite into it. Because real gold is softer than fake, if it stays intact then it is fake.
6. Use the streak method. Take the gold and streak it across an unglazed piece of porcelain. If it is black, it is fool's gold, but if it is goldish-yellow, it is real.
7. Another test is the hardness test. According to Moh's scale, you should not be able to scratch glass with gold, but with fake gold, such as Pyrite, you should be able to.
8. Pyrite, which is fake gold, if magnified 10 times, is actually made out of tiny cubes.
9. When gold is hammered, it will not break, but might bend. However, if Pyrite is smashed, it will break into tiny little cubes.
10. You can take it into a shop where they can test if it is real gold. This is an inexpensive way and it takes only a short amount of time.

Answered by Priyanka C , an ibibo Master, at 6:32 PM on January 09, 2009

Hi Kunnu,

Platinum is rarer, heavier, more durable and even more expensive than gold. It is also very dense, therefore showing fewer scratches and requiring MUCH LESS UPKEEP than other precious metals! The appeal of platinum is in its appearance. Its white luster is unique and also the strongest precious metal. It is almost twice as heavy as 14-karat gold. The metal appears silvery-white when pure, and firm. The metal is corrosion-resistant. If you suspect a fake, bounce the jewelry in your hand and judge how heavy it feels in comparison to a gold jewelry. If it feels a lot heavier, it probably is platinum.

Answered by Amit Suri , an ibibo Master, at 6:25 PM on January 09, 2009

Platinum is rarer, heavier, more durable and even more expensive than gold. It is also very dense, therefore showing fewer scratches and requiring MUCH LESS UPKEEP than other precious metals! The appeal of platinum is in its appearance. Its white luster is unique and also the strongest precious metal. It is almost twice as heavy as 14-karat gold. The metal appears silvery-white when pure, and firm. The metal is corrosion-resistant. If you suspect a fake, bounce the jewelry in your hand and judge how heavy it feels in comparison to a gold jewelry. If it feels a lot heavier, it probably is platinum.

Answered by Uttam , an ibibo Master, at 6:23 PM on January 09, 2009