Kerin Cornelius, age 7, of Huntsville, Alabama, for her question:
Where do they get platinum?
You might find small amounts of silvery platinum in Nevada or California, in Oregon or Ontario. But you would have to search in certain rich mining regions where they dig for gold and copper and other valuable metals. A few lucky people have found big chunky nuggets of precious platinum.
Platinum is one of the earth's most useful and most valuable metals. It is as scarce as gold and, like gold, it is found in the ground. The steely gray metal may come in small grains or flat flakes and here and there it comes in pebble sized nuggets. The biggest platinum nugget was found in the Ural Mountains of Russia in 1916. It weighed 21 pounds and then such a lucky find was worth more than $60,000. Nowadays, the value of such a find would be only around $26,000.
About 400 years ago, someone discovered that no other metal is quite like it. But no one paid much attention or gave it much value. Some 200 years ago, the Spanish explorers of South America found lots of it but they did not know its value. They hoped it was silver and named it platinum, which means little silver. Later the silvery metal was tested and experts discovered that it was much harder and more durable than silver. These and other good qualities made it useful and because it is so hard to find, platinum became precious. The platinum miners of Colombia and other parts of South America became rich.
Most countries have no platinum at all. Rich mines were discovered in the Ural Mountains and until World War I, most of the world supply came from Russia. Then platinum was found mixed with the gold in certain mines of South Africa. Most deposits were found in the copper mines of Sudbury in Ontario, Canada, and another supply was discovered on tie faraway island of Borneo. A little platinum is mined with other valuable metals in Colorado, Oregon and California.
The sturdy metal is rust proof, heat proof, and so easy to work with that it can be drawn in threads 30 times thinner than a human hair. But even if we could afford it, the earth does not have enough platinum for all the things we would like: to do with it. Most of the handsome, durable metal is shaped into jewelry and settings for diamonds. Every year, the United States uses about 15 tons of platinum for jewelry and delicate pieces of machinery and electrical equipment. But we mine only 1 1/2 tons from our own deposits.
The other 13 1/2 tons must be bought from other countries that mine more platinum than they use.
A pail of platinum may be 19 times heavier than a pail of water and a platinum spoon is almost twice as heavy as one of silver. In the ground, some platinum is mixed with a little iron but some deposits are almost pure metal. It is found in ancient lava beds, often mixed with grains of gold or copper. There fire formed rocks may contain fragments of platinum mixed with iridium and osmium, rhodium and palladium. Some of these strange sounding metals are rarer than platinum and even more valuable.
Platinum is a catalyst material, which means that it can cause other chemicals to change without changing itself. It is used as a catalyst to make sulphuric acid and high octane gasoline. It is used in delicate electrical, gadgets and if light bulb filaments could be made of platinum they would last for years. Platinum mixed with other metals makes some of the hardest alloys. Standard weights and measures are made from an alloy of platinum and its sister metal, iridium.