most severe are the platinum group metals, as they have the highest density.Among them, the most difficult - osmium and iridium.It is the hardest material.Indicator densities of these metals is almost the same, except for a minor computational error.
discovery of iridium was in 1803.He found the English chemist Smithson Tennat exploring the natural platinum, delivered from South America.Translated from the Greek name "iridium" means "rainbow".
Get hardest metal (iridium) is very difficult, it is almost not exist.Often considerable amount found in meteorites that have fallen to the ground.According to most scientists, the content of iridium on the planet should have been much more.But due to the special properties of metal - siderophilic (similarity with iron), he sank into the depths of the Earth's interior during the process of the formation of Earth's core.
Iridium - the solid metal, which is very difficult to treat as a thermal and chemical process.It does not react with acids, combinations of acids at a temperature of less than one hundred degrees.This metal is susceptible to oxidation is lowered into a solution consisting of a mixture of hydrochloric and nitric acid (aqua regia).
scientific interest as a source of electrical power is a heavy metal isotope - iridium-192m2, as the half-life of this metal is very large - 241 years.Widespread use of iridium found in industry and paleontology - it is used for the production of feather pens, determining the age of the Earth.
Opening osmium occurred randomly in 1804.This is the solid metal was found in the chemical composition of the sediment dissolved in aqua regia platinum.The name "Osmium" comes from the Greek word "smell".The nature of the metal is almost there.Most often it is found in the composition of complex ore.As well as iridium, osmium hardly susceptible to mechanical abrasion.One liter of osmium is much heavier than ten liters of water.But this property this metal is still nowhere to be found application.
most solid metal osmium extracted from the Russian and American mines.However, the richest deposit of its recognized South Africa.Often osmium found in the composition of iron meteorites.
particular interest is the osmium-187, exported only Kazakhstan.It is used to determine the age of meteorites.One gram of this isotope is 10 thousand. USD.
The industry is mainly used hard alloy of osmium and tungsten (Osram) for the manufacture of incandescent lamps.Osmium is also a catalyzing agent in the production of ammonia (ammonia).Enough of this rare metal fabricated parts for cutting tool in surgery.
Both heavy metal - osmium and iridium - almost always contained in a single alloy.This is a definite pattern.And for their separation is necessary to work hard, because they are not as soft as, for example, silver.