A spark plug is one of the most important parts of a petrol engine. It provides a spark into the fuel-air mixture at high pressure in the combustion chamber. It causes its ignition causing an expansion and there by power is generated.

Until recently Platinum was considered the best material to use on the top of an electrode of the sparkplug, because of its durability. How ever Iridium is 6 times harder, 8 times stronger and has a melting point of 1200 degrees higher than Platinum. Put that into a harsh environment such as an engine piston chamber and you have a spark plug that can resist wear much better than Platinum. Iridium is one of the most unique minerals known to man. this silvery white metallic substance, which occurs as a solid at room temperature, has a very interesting history. Approximately some 50 million years ago an asteroid around 10 km in diameter slammed into what is now Mexico's Yucatan Peninsula. This is what scientists summarize as the phenomenon, which brought about the ice age, which resulted the extinction of all life forms on earth, mainly Dinosaurs. The evidence for this has been known for sometime, with deposits of Iridium rich clay found at the boundary of cretaceous and tertiary deposits, known as K/T boundary, found all over the world.

The ability of iridium to be used in manufacture type environment is unique. some products that use Iridium are cellular phones, sunglasses and our primary concerns spark plugs. The reason for only a few companies using this precious metal is its difficulty to manipulated in a cost effective manner. iridium complemented by rhodium increases oxidation wear resistance making it ideal for electric circuits and is where it comes into play in spark plugs. so what makes Iridium the best for spark plugs?

Let's delve a little into the intricacies of spark plug. an optimum spark plug to generate very high temperature spark to ignite fuel-air mixture as quickly as possible. The shape of the plug electrode is pivotal here. The sharper the electrode the easier it is to ionize air between them and thus enhancing combustion. iridium alloy is so far more durable than Platinum, and makes allowances to produce extremely center electrodes, which reduces the voltage requirements, concentrating its sparking power. iridium is generally best used for high rpm normally aspirated engine. because of high melting point (2410 degree Celsius to 1772 degree Celsius of platinum) Iridium can have very sharp tips without risk of melting and can last a long time.