which layer is a very dense, solid mixture of iron and nickel
A layer about 2885 km thick with density increasing with depth from 3.3 - 5.4 g cm-3. It is solid and is thought to consist of peridotite (an iron / magnesium-rich silicate rock). Outer core. A layer 2255 km thick which is very dense, increasing with depth from 9.9 - 12.3 g cm-3. It is liquid and probably consists of an iron and sulfur mixture. Inner core. This has a 1215 km radius and is very dense, with a maximum density of 13.5 g cm-3. It is solid, and is thought to consist of an iron and nickel mixture. Table 2 The main properties of the layers of the Earth. Students complete written answers to the worksheet Structure of the Earth: the story of the waves.