Early English colonists to America named both the James River and the Jamestown colony after King James the I.

When a stalagmite reaches a stalactite or the top of a cave, the resulting formation is called a column.

Most caves are formed when water creeps through cracks into limestone and eats away at it with natural acids, forming an open space inside the ground.

Petroleum is a mixture of thousands of tiny substances called hydrocarbons.

The Navajo are the largest current tribe of Indians in the United States.

Emerald is created when traces of chromium are found in beryl.

Rubies and sapphires are both formed when traces of a certain metal (for rubies, chromium, for sapphires, iron or titanium) are found in the mineral corundum.

Marble is created when limestone is put under extreme heat and pressure.

Pumice is formed from gas-filled lava, leaving hollow spaces full of air in the pumice that makes it light enough to float on water.

Mt. St. Helens is what is known as a composite volcano, which is formed by alternating layers of lava and tephra.