Explore Earth's structure, rocks, minerals, and geological processes
Granite, Basalt
Limestone, Sandstone
Quartz: SiO₂, Hardness 7, Hexagonal
Calcite: CaCO₃, Hardness 3, Trigonal
Pyrite: FeS₂, Hardness 6.5, Cubic
Magnetite: Fe₃O₄, Hardness 6, Cubic
Olivine: (Mg,Fe)₂SiO₄, Hardness 7, Orthorhombic
Phanerozoic Eon (541 Ma - Present)
Proterozoic Eon (2500-541 Ma)
Archean Eon (4000-2500 Ma)
• Earth's crust is 99% composed of 8 elements
• Ocean floor is recycled every 200 My
• Diamonds form 150-200 km deep
• Granite makes up 70% of continental crust
• Fossils preserve life from 3.5 billion years ago