A scholar named Vander Gracht has described four layers of the earth’s internal structure.
These layers are classified as follows:
1. Outer silica crust: It is the topmost layer of the earth.
2. Inner silicate layer and mantle: This is the second layer from the top in the internal structure.
3. Layer of mixed metals and silicate: This is the third layer in the internal structure.
4. Metallic center or metallic nucleus: According to Vander Gracht, it is the innermost layer of the Earth.
