|The molten rock expelled by a volcano is called ____.
|The molten rock below the Earth's surface is called ____.
|Minerals are identified by their hardness and ____ (powder color).
|Volcanic ____ is the product of rapidly cooling lava.
|Quartzite is a rock, whereas quartz (silicon dioxide) is a ____.
|Mount Rushmore is a granite ____ formation in South Dakota.
|Carbon, copper, silver, and sulfur are single ____ minerals.
|The Mohs scale is used to measure the ____ of a mineral.