Geology

Learn about geology. Topics include minerals, Earth science, volcanoes, rocks, and important geological cycles.

Sea Glass and Beach Glass — Learn about sea glass and beach glass. See how they form, the colors and their rarity, and how to tumble glass yourself.

Sea Glass and Beach Glass

This entry was posted on July 12, 2022 by Anne Helmenstine (updated on July 18, 2022)

Gem vs Mineral — Learn the difference between gems and minerals. See examples of gemstones and their minerals. Explore precious and semiprecious gems.

Gem vs Mineral – Difference Between Gemstones and Minerals

This entry was posted on June 11, 2022 by Anne Helmenstine (updated on June 19, 2022)

Difference Between Rocks and Minerals — Learn the difference between rocks and minerals. Get their definitions and examples and also learn about mineraloids.

What Is the Difference Between Rocks and Minerals?

This entry was posted on May 28, 2022 by Anne Helmenstine (updated on June 11, 2022)

Layers of the Atmosphere — Learn about the 5 main layers of the atmosphere and also the sublayers. See the height, temperature, and composition of the layers.

Layers of the Atmosphere

This entry was posted on May 3, 2022 by Anne Helmenstine (updated on May 12, 2022)

Mohs Hardness Scale — Learn about the Mohs hardness scale and see how diamond, fingernail, and other materials rank. See examples of mineral hardness values.

Mohs Hardness Scale

This entry was posted on March 6, 2022 by Anne Helmenstine (updated on July 17, 2022)

Zircon vs Cubic Zirconia — Learn the difference between zircon and cubic zirconia and how to tell them apart as gemstones for jewelry.

Zircon vs Cubic Zirconia

This entry was posted on February 26, 2022 by Anne Helmenstine (updated on May 18, 2022)

Blue Lava Volcano — Learn about blue lava. Find out if it's real, how it works, and where to see it. Can't make the trip? Make a blue lava lamp instead.

Blue Lava Volcano

This entry was posted on January 4, 2022 by Anne Helmenstine (updated on January 10, 2022)

What Is a Geode? — Learn what a geode is, how one forms, where to find geodes, and how to open them. Get ideas for making homemade geodes.

What Is a Geode? How to Find and Open Geodes

This entry was posted on April 27, 2021 by Anne Helmenstine (updated on May 6, 2021)

What Is Fulgurite — Learn what fulgurite is. See where to find it and how to make fulgurites yourself using different methods.

What Is Fulgurite? Where to Find It and How to ...

This entry was posted on April 19, 2021 by Anne Helmenstine (updated on May 6, 2021)