Silica as SiO2 (%) 6.94
Iron as Fe2o3 (%) 82.45
Iron as FE (%) 58.48
Aliminium as Al2O3 (%) 0.96
Calcium as CaO (%) 0.46
Magnesium as MGO(%) 0.03
Slate's many virtues make it a popular choice. It has a less formal look than marble or granite. It's extremely durable, slip resistant, stain resistant), and fireproof. It also retains and radiates heat (for use in passive solar homes).
