PRESENTATION OUTLINE
Advantages
Cobalt is a necessary supplement for healthy development. It is also the name for a striking blue colour! Cobalt is an element that is classed as a metal. It is a required component of Vitamin B12. It has also recently been identified as an integral part of blood cell production.
Rhodium belongs to the Platinum group of metals. All of them present outstanding chemical inertness (will not react or change easily) thus, rhodium will not tarnish whereas silver will. They are very expensive, so only a very thin plate is applied to reduce the amount of metal in the jewel. If not subject to excessive friction and wear, they will retain their look indifferent
Since late in the 20th century Iridium has been used in alloy form as material of choice for construction of Spark plug and industrial igniter electrodes. Pure Iridium is difficult to work with, very brittle and does not have great electrical conductivity hence alloys are used to give the best combination of these properties.
At present it is only used in research.
