Geology and Earth Science News and Information

Rhyolite An extrusive igneous rock with a high silica content, produced from granitic magma.

Rocks on Mars Many of the rocks found on Mars are not very different from Earth rocks.

Rocks - Galleries of igneous, sedimentary and metamorphic rock photos with descriptions.

Gifts That Rock - What are the most popular gift items in the Geology.com store?

Free Google Earth software allows you to browse seamless world satellite images. Free.

Cave of the Hands is a cave where ancient people painted hands about 9000 years ago.

The Green River Formation is one of the most famous rock units in the world for its fossils.

Plate Tectonics - Articles and maps about plate tectonics and the interior of Earth.

Chalcopyrite - The most important ore of copper for over five thousand years.

Ilmenite - The primary ore of titanium and source of most titanium dioxide.

Gemstones - Colorful images and articles about diamonds and colored stones.

Meteorites - Rocks that were once parts of planets or large asteroids.

Diamonds - Learn about the properties of diamond, its many uses, and diamond discoveries.

Types of Volcanic Eruptions - A description of the most common eruption types.

The Rock Used to Make Beer - Geologists are beer experts and should know about this rock.

Rock & Mineral Kits The best way to learn about rocks and minerals is with specimens!

Quartzite is metamorphic rock formed when sandstone is subjected to heat and pressure.

Fire Opal is a transparent to translucent opal with a yellow, orange or red background color.

Copper is a metal used in coins, electronics, pipes, wiring, motors, alloys and many other products.

Volcanoes - Articles about volcanoes, volcanic hazards and eruptions past and present.

Spatter Cones are small, steep, volcanic cones built of welded basaltic lava.

Debris Flows are moving masses of loose mud, sand, soil, rock and water.

The Uses of Marble are numerous and diverse. You will be surprised by how it is used.

Andalusite is a metamorphic mineral and a strongly pleochroic gem material.

Crater of Diamonds - The only diamond mine in the world where you can be the miner.

Rare Earths - Special materials used in electronics, defense, medical & many other products.

Extraterrestrial Gems - A number of materials from space are used as attractive gems.

Minerals - Descriptions, photos, articles, properties and uses for common minerals.

Obsidian - the volcanic rock that cools so quickly that it becomes a natural glass.

Bear Attacks - Knowing how to react to a bear encounter or attack could save your life.

Hardness Picks - Test for hardness with precise and easy-to-use hardness picks.

Types of Maps - Explore some of the most popular types of maps that have been made.

Where Are the Canary Islands? Off the northwest coast of Africa, 60 miles west of Morocco.

Helium is a byproduct of the natural gas industry. Its most important use is in MRI.

Wall Maps - Wall maps of the world, continents, states and the USA.

What Is Luster? Luster is the light-reflecting characteristics of a mineral specimen.

Fool*s Gold is a name used for pyrite when its brassy color fools people looking for gold.

Pyroxene Minerals are a group of chain silicate minerals found in igneous and metamorphic rocks.

Phytoplankton Blooms are caused by an explosive growth rate of plankton in surface waters.

Crystal Habit is the external shape displayed by a crystal or an aggregate of crystals.

Sand is a diverse material. This gallery includes photos of sand from around the world.

Mohs Hardness Scale is a set of reference minerals used for classroom hardness testing.

Pictures of Opal - A collection of different types of opal from all around the world and Mars too!

Zircon is the primary ore of zirconium and a gemstone that is available in many colors.

Ruby and Sapphire are the 2nd and 3rd most popular colored stones in the United States.

Blue Flames and the largest highly acidic lake in the world at Kawah Ijen Volcano.

Largest Hurricanes Are they determined by wind speed, value of damage, most deaths?

Map of the Oceans - showing the Atlantic, Pacific, Indian, Arctic, and Southern Oceans.

Granite - The intrusive igneous rock that underlies continents and countertops.

Teacher Resources - K-12 resources for teaching about earth science.

Rock Tumblers - All about rock tumblers and rock tumbling. Read before you buy a tumbler.

Cinnabar - the only important ore of mercury. Used in pigments until its toxicity was realized.

World Record Lightning - this lake has more lightning than any other place in the world.

Birthstones are gems assigned to the month of a person*s birth. They are popular gifts in the U.S.

Tallest Tsunami - A wave with a run-up height of 1720 feet occurred in Lituya Bay, Alaska.

What is the San Andreas Fault? Map, photos and description of the fault.

Hand Lens A 10-power folding magnifier in a metal case. A frequently used lab and field tool.

Mineraloids are amorphous naturally-occurring inorganic solids that lack crystallinity.

The Acid Test - Geologists use dilute hydrochloric acid to identify carbonate minerals.

Coquina - A porous limestone composed almost entirely of fossil debris.

Largest Earthquake ever recorded - Magnitude 9.5. Chile, 1960.

Labradorite is a feldspar mineral that sometimes exhibits an iridescent play-of-color.

Colored Diamonds are diamonds with a noticeable body color. They can sell for over $1M/carat.

Volcanic Explosivity - Rating volcanic eruptions based upon the volume of tephra ejected.

Topo Maps - The DeLorme Atlas is an entire state of topo maps in one convenient book.

Geology Tools - Rock hammers, field bags, hand lenses, maps, hardness picks, gold pans.

Ethiopian Opal - The new opal heavyweight that might give Australia a run.

Portable UV Lamp - Short and long wave UV for fluorescent mineral viewing.

Lapis Lazuli - a metamorphic rock and the most popular blue opaque gemstone in history.

Solar System Volcanoes - Earth is not the only location of volcanic activity.

Fluorescent Minerals and rocks glow with spectacular colors under ultraviolet light.

Geology Books - A variety of books for reference, field trips, reading and more.

Novarupta - The most powerful volcanic eruption of the 20th century occurred in the U.S.A.

Field Courses - Over 80 field courses for undergraduate geology students.

Utica Shale is a major source of oil, natural gas and natural gas liquids in PA, OH and WV.

Mount Etna - The most active volcano in Europe continues an eruption that started in 2001.

Gold Pans and Panning Kits - classifiers, snuffer bottles. Learn how to pan for Gold.

What is Geology? The study of Earth materials, structures, processes and life over time.

Rhodochrosite - a manganese mineral used as an ore, a pink gem and an ornamental stone.

Sliding Rocks Mystery - What causes these rocks to slide across a playa in Death Valley?

Soapstone is a metamorphic rock with properties that make it suitable for a variety of projects.

Hematite - The most important ore of iron. A source of mineral pigment since prehistory.

10 Gemmy Facts About Spinel - Is spinel the world*s most overlooked gem?

Mars Meteorites Mars rovers have found dozens of meteorites while exploring the red planet.

Emerald is the most popular green gemstone in the United States and most of the world.

Shale - The rock that has quickly transformed the oil and gas industry.

Lightning Strikes Map by NASA shows the worldwide distribution of lightning activity.

Rock Art - People have been marking on rocks for thousands of years.

Corundum is the third hardest mineral. It is also the mineral of ruby and sapphire.

Know the Rules before removing rocks, fossils or minerals from public or private property.

Tallest Mountain - Everest has rivals in tallness, altitude and distance to the center of Earth.

Ticks are a problem for geologists in some areas. Learn to recognize and avoid them.

Storm Surge can be the most damaging and deadly aspect of a hurricane.

Morganite is an orange to pink gemstone, a variety of beryl, that is growing rapidly in popularity.

Olivine - Abundant in Earth*s mantle. A constituent of meteorites. The gem peridot.

US Diamond Mines - Did you know that diamonds have been mined in the United States?

The Science of Fireworks Learn how the colors and shapes are created.

Mined in America - Small mines in the United States produce a diversity of beautiful gemstones.

Range of Bear Species - Where you might encounter different types of bears.

Citrine is the transparent variety of quartz with a yellow to orange to reddish color.

Rock Salt is a sedimentary rock composed of the mineral halite. It has many uses!

Expansive Soil causes more damage than floods, hurricanes & tornadoes combined.

Waterproof Paper - Don't take chances with your field notes and maps. Use waterproof paper.

Gem Silica is a blue chalcedony colored by copper. It is the rarest and most valuable chalcedony.

Hawaii*s Next Island could be growing in the Pacific Ocean right now. Its name is Lo*ihi.

Petrified Wood is a fossil that forms when silica replaces and infills the cavities of wood.

100+ Gems - Photos of over 100 beautiful gems ranging from the popular to the obscure.

What Is Earth Science? The study of Earth and its neighbors in space. Learn more!

Diamond Misconception - Many people think that diamonds form from coal. Not True!

Angel Falls in Venezuela is the tallest waterfall in the world - it is 3212 feet tall.

Mineral Rights - Who owns the minerals under your land? Who wants to buy them?

Coal Through a Microscope - Coal is more than a black rock. It is THE most interesting rock.

The East Africa Rift System - The extensive fault system that is tearing Africa apart.

The Many Uses of Gold - Unique properties make gold one of the most useful metals.

What is a Geyser? Photos and information about geysers in many parts of the world.

Ant Hill Garnets - tiny gems that ants haul to the surface and discard on their anthill. Honest!

Grape Agate is a popular mineral specimen with the color and the shape of a bunch of grapes.

Turquoise - A bluish-green gem material that has been used for over 6000 years.

Talc is a soft mineral used in cosmetics, paper, paint, ceramics and many other products.

What Is The Moho? The Mohorovicic Discontinuity is the mantle/crust boundary.

Names Used for Great Britain, British Isles, United Kingdom, and Ireland. What they mean.

World*s Largest Diamonds Records for the largest rough, faceted and carbonado diamond.

Azurite - Used as an ore of copper, a pigment, ornamental stone and gem material.

How Are Hurricanes Named? There is a plan for naming tropical storms.

How did the Hawaiian Islands Form? The power of a moving plate over a stationary hot spot.

Tourmaline - an extremely colorful mineral and gem material.

Geodes look like ordinary rocks on the outside but can be spectacular inside!

Peridotite is a chromite host rock, a source of diamonds and a possible carbon dioxide sink.

What is a Maar? The second most common volcanic landscape feature on Earth.

California Earthquake Maps - A collection of isoseismal maps for earthquakes in California.

Charoite is a purple silicate mineral, found only in Russia, used as a gem material.

Herkimer Diamonds Doubly-terminated quartz crystals used as specimens and gems.

The Unsung Mineral Hero - and the commodity upon which almost everything is built.

Homeowners Insurance might not cover earthquake, hurricane and other geohazard damage.

Largest Volcano - That title is shared by Tamu Massif, Mauna Kea and Ojos del Salado.

Tanzanite was unknown until a few decades ago but it has erupted into wide popularity.

Mount Vesuvius - geology, history, maps, facts and more about the Vesuvius eruptions.

Deepest Point in the Ocean The deepest point in the ocean is in the Mariana Trench.

Cinder Cones are the smallest, simplest, and most common type of volcano.

Chalk is a variety of limestone formed from fine-grained marine sediment known as ooze.