The familiar expanding-Earth animation is an optical illusion based on a conceptual illusion.
Float - loose rocks in the soil - can yield useful geologic information in areas where the bedrock is hidden.
Start here for the seismic basics: faults that cause earthquakes, types of seismic waves, damages they cause and more.
Understanding geologic maps starts with topography.
Thirty-five states have official gemstones. Here they are, listed by state.
Big list of mineral names and their corresponding gemstone names.
Geothermal energy exploits the Earth's natural heat budget.
Americans don't burn coal at home any more, but it still works for much of the world.
Is it so strange to bring a stone back to the place I got it from?
A survey of 9 mineral substances whose properties make them useful abrasives.