Iridium is a very hard, heavy, rare and expensive silvery metal and the most noble of all metals. It hardly reacts, but as a fine powder it is flammable. It is used is special alloys and as a catalyst. The meteorite, which 65 million years ago played a key role in the extinction of the dinosaurs, contained relatively much iridium. This can still be observed in sediment layers from this time.
<p>Hi-Res Images of
</p>
Chemical Elements
CC BY 3.0
<a rel="nofollow" class="external free" href="http://images-of-elements.com/iridium.php">http://images-of-elements.com/iridium.php</a>