Geochemistry & Petrochemistry

This is a list of pictures of minerals, including mineral crystals, rough specimens, and minerals that have been cut for use as gemstones.

This is a collection of photographs of crystals. Some are crystals you can grow yourself. Others are representative pictures of crystals of elements and minerals.

This alphabetical list of gemstones includes the mineral names of the gemstones as well as links to photos of the gems.

Petroleum or crude oil is a complex mixture of hydrocarbons and other chemicals. Here is a look at the properties and chemical composition of petroleum.

This is the definition of petroleum, also known as crude oil.

Yellowstone National Park contains many fascinating and beautiful geothermal features. Learn about the geochemistry of the park and view the spectacular scenery resulting from the extraordinary geysers and hot springs.

You probably know the sun consists mainly of hydrogen and helium. Can you name the other elements found in our closest star?

Learn about the two main types of rock tumblers and get some selection tips and helpful advice to prepare for your first tumble. Links to related resources and support sites are also included.

Gemstones are minerals that can be polished or cut for use as an ornament or jewelry. The color of a gemstone comes from the presence of trace...

Carbon is an element that is essential for life. The carbon cycle describes the storage and exchange of carbon between the Earth's biosphere, atmosphere, hydrosphere, and geosphere.

Learn about the processes involved in the nitrogen cycle, the biochemical cycle that describes the transformations of nitrogen as it goes through nature.

Minerals are natural inorganic chemical compounds. These are photographs of minerals, along with a look at their chemical composition.

Do you want to take great pictures of your mineral specimens? Here are some tips and tricks to help your mineral photos turn out looking wonderful.

Do you know about the chemistry of rocks and minerals? Here's a ten question quiz you can take to test your knowledge.

The Mohs Scale of Hardness measures how well a substance resists scratching by another material. You can use this scale to test the hardness of rocks, minerals, and crystals, to help identify them.

The Mohs test is one way to determine the hardness of a rock or mineral. You can use the Mohs hardness to help identify an unknown specimen. Here's how you can do the test yourself.

Here are instructions for tumbling rocks using a rotary drum tumbler and a vibratory tumbler, as well as instructions for polishing jewelry in a rock tumbler. Helpful tips are included for improving the polish and troubleshooting problems.

Here are some science fair project ideas that involve plants and soil chemistry. Are you looking for an environmental science project? Check here!

Learn about what fulgurites are and how they form.

See photos of rough and cut gemstones and learn about the chemistry of the minerals.

This is a photo gallery of lightning and plasma pictures.

Here's a quick and easy science project you can do: make a cloud inside a bottle. This simple project uses water vapor and smoke from a match to help form a cloud.

Hawaii's Green Sand Beach is an unforgettable destination. Learn why the sand is green and how to get to the beach.

Hawaii boasts many black sand beaches. Learn more about why the sand is black.

Take a look at the Big Island of Hawaii from a chemistry perspective.

The Emerald Hollow Mine in Hiddenite, NC is the only emerald mine in the United States open to the public for prospecting. I went to North Carolina to check the mine out for myself. Can you find emeralds? Yes! And rubies, sapphires, amethyst, citrine, the rare gemstone hiddenite, and much more.

Test your knowledge of the metals with this ten question quiz. Links about different metals are provided to help you find the answers.

Part I: Carbon Chemistry and Diamond Crystal Structure, emphasizes diamond formation and crystal structure. Part II: Properties and Types of Diamonds, dicusses diamond characteristics, classification system, and methods of synthesis. There are also links to learn about carbon allotropes, diamond mining, diamonds as gemstones, and geology.

This table shows the chemical composition or abundance of chemical compounds in the Earth's crust.

Let's take a look at the two main ways to categorize crystal types. I've described the major crystal structures (e.g., triclinic, hexagonal) and how crystals are classified by their properties (e.g., ionic, covalent) and provided links so that you can see examples of crystal types and learn more about crystallography.

This twin-barrel rock tumbler from Lortone features rubber 3 lb. capacity barrels, a fan-cooled continuous duty motor, and durable metal housing. This summary itemizes the tumbler's features and includes a product evaluation.

This kit includes everything except the boiling water needed to grow eight colors of large crystals, geodes, clusters, and more! Find out what is included in the Smithsonian Crystal Growing set and how it works in actual use.

Are you considering getting a rock tumbler? Before you make a purchase, learn about the different types of rock tumblers and get tips on choosing the best tumbler for your needs.

The elemental composition of the universe and the earth's crust are very different! How different? Take a look...

Learn about chemical composition of the Earth's air. Percentages of the most common compounds are given, according to volume.

Have you ever wondered why the ocean is salty? Have you wondered why lakes might not be salty? Here's a look at what makes the ocean salty and why other bodies of water have a different chemical composition.

Here's the scale used to assess a stone's ability to resist abrasion. Both gemstones and some everyday items are included.

Specific gravity expresses the relative density of a material relative to the density of water. Here's a table of specific gravity ranges for several minerals.

This is About's comprehensive guide to earth science, with articles, links, and resources.

This is an illustrated dictionary of jewelry, but it is a great reference for quick information about gemstones, metals, and minerals.

This is the homepage for the Geochemistry Department of the Geological Survey of Japan. The site is available in either English or Japanese.

The IZA website promotes and encourages the development of all aspects of zeolite science and technology. There are links to publications, commissions, announcements, conferences, and links.

Chemistry, characteristics, and identification of minerals. From Amethyst Galleries.

Visible, infrared, and Raman spectra of minerals. From George R. Rossman, California Institute of Technology.

Lectures involving origination of and chemical processes within igneous and metamorphic rocks. From Greg Finn, Brock University.

Introduction to every facet of snowflake formation. From Kenneth G. Libbrecht, California Institute of Technology.

Projects may be located by title, investigator, region, or topic. Proposals, data, abstracts, publications, and other information is also available.

Keyword search finds data on domestic and foreign mineral production and consumption. From the US Geological Survey.

This is a table that shows the elemental chemical composition of the Earth's crust.

Have you ever wondered what would happen if you mixed regular and synthetic motor oils? Here's the answer to the question and a look at whether it's okay to mix motor oils.