Overview of diamonds explores their composition, crystal structure, hardness, durability, dispersion, refraction, color and surface properties.

Discusses the hardness, clarity, thermal conductivity, physical characteristics, and melting point of diamonds.

Univ. of Bristol provides a guide to diamonds and graphite. Learn the difference between the two substances and see their molecular structures.

Learn how diamonds are formed and cut, and read about some of the world's most famous diamonds.

Dept. of Materials Science at the Univ. of Arizona offers a guide to diamonds. See the molecular structure and learn about the cheimical bonds.

Learn about the element carbon, including where it is found and the difference between graphite and diamonds, and see its molecular structure.

Look at specimens of the mineral diopside, review its physical characteristics and learn its uses.

Find out this substance's composition and essential properties, and discover how it is used by man. View photos of samples.

Consult this encyclopedia entry to learn about this mineral and its chemical makeup.

Profiles this prized green gemstone, with details on its composition, crystalline structure, and varieties. Includes photos of samples.

Find out what makes an emerald green and why this gem has historically been mined in Egypt.

Fine granular substance is mined in the US and Turkey. Learn about its common uses.

See photos of this common mineral composed of potassium, sodium, and calcium that eventually erodes into clay.

Introduces this mineral family and provides details on such members as orthoclase, microcline, albite, and labradorite.

Discover this lead ore's chemical composition, its properties and uses, and its geographic distribution. View photos of samples.

Learn about this dark gray crystal found in the eastern and central US.

Check out the different forms of this gemstone found around the world.

Discusses the varieties of this semiprecious stone, providing details on their composition and properties, and links to related minerals.

Find out how to identify, cut, and engrave gemstones. Includes a gemstone association.

Find out how the spheres of multiple layered quartz are formed.

Peruse facts and figures on this precious metal, including details on its ores and the areas it is mined. View a photo of a sample.

Get an overview of physical properties of this precious metal, locations of its occurrence, and mining methods.

John Jaszczak provides an introduction a common mineral called graphite which is seldom represented in collections. With images and descriptions.

Identifies this carbon variety's chemical structure and locates its geographic sources. Features a photo of the mineral in its natural state.

Describes the formation and composition of this useful carbon deposit.

Describes the substance known chemically as hydrous calcium sulfate. Provides several photos of the mineral in its natural state.

Groups alabaster, selenite, and satin spar under the category of gypsum.