Thursday, June 29, 2006

Powerful Platinum

Symbol: Pt
Melting Point: 1774 degrees C & 3225 degrees F
Specific Gravity: 21.4
Hardness: 4-4.5


Originally, platinum was discovered by the Spanish explorers in Columbia, South America in 1538. They called it platina because it looked similar to silver (called Plata). Believe it or not, at one time, people didn’t know what to do with platinum. They used it for pots and pans. It didn’t become a popular jewelry metal until the early 1900s. Then during World War II, the U.S. government banned the use of platinum in jewelry making, and white gold was used instead. However, it has become popular again for a number of reasons. First, it is a very dense white metal that resists tarnishing. Platinum jewelry has little alloy in it, usually only 10%, so it is considered hypoallergenic.

There are six metals which belong to the platinum family:

platinum
palladium
rhodium
ruthenium
iridium
osmium

All these metals require oxygen to be mixed with the fuel when melting since they have such a high melting point. They resist tarnishing and do not require flux when soldering. Metals in this group can also be cast, but because of their high melting point, a special investment must be used.

Today, most platinum used in jewelry in mined in Russia which controls the amount minded (much like the diamond industry). A large percentage of platinum is used in jewelry making. However, it is also used in other industries such as the medical industry and the automotive industry.