Magnesium has several key properties that make it an attractive base metal for wheels: lightness; a high damping capacity; and a high specific strength. Magnesium is the lightest metallic structural material available. It is 1.5 times less dense than aluminum, so magnesium wheels can be designed to be significantly lighter than aluminum alloy wheels, while exhibiting comparable strength. All competitive racing rims are now made of magnesium alloy.
According to Wikipedia, a notable disadvantage historically affecting magnesium wheels was their susceptibility to corrosion.
The Maserati Merak wheels have been somewhat of a challenge to us at Bridge Classic Cars. When they originally arrived to us, they, along with the entire car, was looking in a very sorry state.
After carrying out a full restoration on the wheels they are now looking much better but still not perfect so we have given ourselves a second chance with them.
Today we have started to strip them back to bare metal (by hand) to start the process once more. These are not like your regular alloy wheels so the regular treatment you would normally be able to do does not bring them up as good as they can be.
Stripping them back reveals the corrosion and pitting that has occurred over years, it then gives us the opportunity to repair the areas before reapplying the top coat. This should give a much cleaner, crisp finish.