Approximately 4,000 mineral species have scientists identified.

A bar chart is a collection of price bars, with each bar showing price movements for a given period.

The rock cycle is driven by two forces: (1) Earth's internal heat engine, which moves material around in the core and the mantle and leads to slow but significant changes within the crust, and (2) the hydrological cycle, which is the movement of water, ice, and air at the surface, and is powered by the sun.

A bar chart or bar graph is a chart or graph that presents categorical data with rectangular bars with heights or lengths proportional to the values that they represent.

A line graph is a type of chart used to show information that changes over time.