Nowadays, thousands of people pay attention to this question.
Why?
Because gold is a non-renewable resource and it’s very expensive. In the past, people will bite the medal, especially the champion to make sure it is real gold.
But now because of the high price of real gold, most of the medals are not made of full gold(including the Olympics), such as the 2008 Olympics medal, each gold medal contains no less than 6 grams of gold.
Normally, the material of the medal is zinc alloy, copper, aluminum, stainless iron, and iron. To make them look like gold or silver, we will do the planting, and after planting medals looks like gold or silver medals.
(GETTY IMAGES ASIAPAC)
What are the differences between these materials?
Zinc Alloy
Advantages of Zinc Alloy
1. High plasticity 2. Recyclable recast
3. Anti-corrosion 4. Easy to operate
5. Suitable for plating 6. Low cost
The disadvantage of Zinc Alloy
Surface blistering
Copper
Advantages of Copper
1. Wear-resisting 2. Chemical stabilization
The disadvantages of Copper
1. Expensive 2. Heavy
Aluminum
Advantages of Aluminum
1. light 2. Easy to operate
3. Large production 4. Oxidizing layers protect objects
The disadvantages of Aluminum
1. Low density 2. Easy to deformation
3. Not corrosion-resistant, not wear-resistant
Stainless Iron
Advantages of Stainless Iron
1. Strong corrosion resistance 2. Large hardness, not easy to deform 3. Metallic
The disadvantage of Stainless Iron
Have burrs
Iron
Advantages of Iron
1. Have a good sense of hierarchy 2. Cheap
The disadvantage of Iron
Easy to rust
(IOC)
Different materials correspond to different molds and processes, zinc alloy medal needs a Square mold, there are small openings around the mold to facilitate the injection of liquid zinc alloy, which is then die-cast.
Other materials need a circular mold, factory workers use a loud press machine to strike the mold with 550 tons of force - three times - to create your medal appearance.
Statements： The first image from 2008 Getty Images