Pictures of Opal - A collection of different types of opal from all around the world and Mars too!
Ukraine is an independent state in eastern Europe that shares a border with Russia to its east.
Deepest Point in the Ocean The deepest point in the ocean is in the Mariana Trench.
The Many Uses of Gold - Unique properties make gold one of the most useful metals.
Corundum is the third hardest mineral. It is also the mineral of ruby and sapphire.
Dig for Gems at dozens of sites across the United States. Keep what you find at most locations.
Azurite - Used as an ore of copper, a pigment, ornamental stone and gem material.
Ant Hill Garnets - tiny gems that ants haul to the surface and discard on their anthill. Honest!
Soapstone is a metamorphic rock with properties that make it suitable for a variety of projects.
Rocks - Galleries of igneous, sedimentary and metamorphic rock photos with descriptions.
Crystal Habit is the external shape displayed by a crystal or an aggregate of crystals.
Sand from Around the World . A photo gallery showing the diversity of the material we call "sand".
Peridotite is a chromite host rock, a source of diamonds and a possible carbon dioxide sink.
Labradorite is a feldspar mineral that sometimes exhibits an iridescent play-of-color.
Diamond Misconception - Many people think that diamonds form from coal. Not True!
Hematite - The most important ore of iron. A source of mineral pigment since prehistory.
What Is The Moho? The Mohorovicic Discontinuity is the mantle/crust boundary.
Minerals - Descriptions, photos, articles, properties and uses for common minerals.
Range of Bear Species - Where you might encounter different types of bears.
Strawberry Quartz is a red to pink quartz with inclusions that look like strawberry seeds.
Five Universal Grinding Wheels 8 x 1-1/2 x 1-1/4" NOLD125FR are diamonds with a noticeable body color. They can sell for over $1M/carat.
Types of Maps - Explore some of the most popular types of maps that have been made.
Wall Maps - Wall maps of the world, continents, states and the USA.
Great Lakes : Map of the Great Lakes with surrounding states and provinces.
Obsidian - the volcanic rock that cools so quickly that it becomes a natural glass.
Free Google Earth software allows you to browse seamless world satellite images. Free.
Lightning Strikes Map by NASA shows the worldwide distribution of lightning activity.
Birthstones are gems assigned to the month of a person*s birth. They are popular gifts in the U.S.
Expansive Soil causes more damage than floods, hurricanes & tornadoes combined.
Shale - The rock that has quickly transformed the oil and gas industry.
100+ Gems - Photos of over 100 beautiful gems ranging from the popular to the obscure.
Rock & Mineral Kits The best way to learn about rocks and minerals is with specimens!
The East Africa Rift System - The extensive fault system that is tearing Africa apart.
Seadoo Jet Ski PWC 00 GTX Millennium, Exhaust Cone 274001108 - Test for hardness with precise and easy-to-use hardness picks.
What is a Geyser? Photos and information about geysers in many parts of the world.
The Rock Used to Make Beer - Geologists are beer experts and should know about this rock.
Granite - The intrusive igneous rock that underlies continents and countertops.
Geology Books - A variety of books for reference, field trips, reading and more.
Plate Tectonics - Articles and maps about plate tectonics and the interior of Earth.
Fluorescent Minerals and rocks glow with spectacular colors under ultraviolet light.
Gem Silica is a blue chalcedony colored by copper. It is the rarest and most valuable chalcedony.
Rock Art - People have been marking on rocks for thousands of years.
Diamonds - Learn about the properties of diamond, its many uses, and diamond discoveries.
Geodes look like ordinary rocks on the outside but can be spectacular inside!
Fool*s Gold is a name used for pyrite when its brassy color fools people looking for gold.
Petrified Wood is a fossil that forms when silica replaces and infills the cavities of wood.
Mineral Rights - Who owns the minerals under your land? Who wants to buy them?
Tallest Mountain - Everest has rivals in tallness, altitude and distance to the center of Earth.
Ethiopian Opal - The new opal heavyweight that might give Australia a run.
What is a Maar? The second most common volcanic landscape feature on Earth.
Portable UV Lamp - Short and long wave UV for fluorescent mineral viewing.
Troglobites are creatures that have adapted to a permanent life in the darkness of a cave.
Geology Tools - Rock hammers, field bags, hand lenses, maps, hardness picks, gold pans.
The Uses of Marble are numerous and diverse. You will be surprised by how it is used.
1983-1991 Toyota 22RE Truck 4Runner Cold Start Valve Fuel Inject is metamorphic rock formed when sandstone is subjected to heat and pressure.
What is Geology? The study of Earth materials, structures, processes and life over time.
Volcanic Explosivity - Rating volcanic eruptions based upon the volume of tephra ejected.
What Is Luster? Luster is the light-reflecting characteristics of a mineral specimen.
What is LNG? Liquefied Natural Gas. The gas is condensed into a liquid for efficient transport.
Largest Earthquake ever recorded - Magnitude 9.5. Chile, 1960.
Types of Volcanic Eruptions - A description of the most common eruption types.
Meteorites - Rocks that were once parts of planets or large asteroids.
Rhodochrosite - a manganese mineral used as an ore, a pink gem and an ornamental stone.
Tourmaline - an extremely colorful mineral and gem material.
World Record Lightning - this lake has more lightning than any other place in the world.
World*s Largest Diamonds Records for the largest rough, faceted and carbonado diamond.
Gemstones - Colorful images and articles about diamonds and colored stones.
How Are Hurricanes Named? There is a plan for naming tropical storms.
Lapis Lazuli - a metamorphic rock and the most popular blue opaque gemstone in history.
Curling Stones are made from a special type of granite, found at just a few locations worldwide.
Herkimer Diamonds Doubly-terminated quartz crystals used as specimens and gems.
Names Used for Great Britain, British Isles, United Kingdom, and Ireland. What they mean.
Zircon is the primary ore of zirconium and a gemstone that is available in many colors.
US Diamond Mines - Did you know that diamonds have been mined in the United States?
Grape Agate is a popular mineral specimen with the color and the shape of a bunch of grapes.
The Green River Formation is one of the most famous rock units in the world for its fossils.
Citrine is the transparent variety of quartz with a yellow to orange to reddish color.
Crater of Diamonds - The only diamond mine in the world where you can be the miner.
Charoite is a purple silicate mineral, found only in Russia, used as a gem material.
Chalcopyrite - The most important ore of copper for over five thousand years.
The Acid Test - Geologists use dilute hydrochloric acid to identify carbonate minerals.
What is the San Andreas Fault? Map, photos and description of the fault.
Olivine - Abundant in Earth*s mantle. A constituent of meteorites. The gem peridot.
Copper is a metal used in coins, electronics, pipes, wiring, motors, alloys and many other products.
10 Gemmy Facts About Spinel - Is spinel the world*s most overlooked gem?
Gifts That Rock - What are the most popular gift items in the Geology.com store?
Map of the Oceans - showing the Atlantic, Pacific, Indian, Arctic, and Southern Oceans.
Andalusite is a metamorphic mineral and a strongly pleochroic gem material.
The Doorway to Hell is a flaming sinkhole seeping natural gas that has been burning for decades.
Mined in America - Small mines in the United States produce a diversity of beautiful gemstones.
Rhyolite An extrusive igneous rock with a high silica content, produced from granitic magma.
Sliding Rocks Mystery - What causes these rocks to slide across a playa in Death Valley?
Volcanoes - Articles about volcanoes, volcanic hazards and eruptions past and present.
What Is Earth Science? The study of Earth and its neighbors in space. Learn more!
Extraterrestrial Gems - A number of materials from space are used as attractive gems.
Mohs Hardness Scale is a set of reference minerals used for classroom hardness testing.
Cave of the Hands is a cave where ancient people painted hands about 9000 years ago.
Turquoise - A bluish-green gem material that has been used for over 6000 years.
Rock Tumblers - All about rock tumblers and rock tumbling. Read before you buy a tumbler.
Rock Salt is a sedimentary rock composed of the mineral halite. It has many uses!
Mars Meteorites Mars rovers have found dozens of meteorites while exploring the red planet.
Angel Falls in Venezuela is the tallest waterfall in the world - it is 3212 feet tall.
Know the Rules before removing rocks, fossils or minerals from public or private property.
Teacher Resources - K-12 resources for teaching about earth science.
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.
Emerald is the most popular green gemstone in the United States and most of the world.
Bear Attacks - Knowing how to react to a bear encounter or attack could save your life.
Homeowners Insurance might not cover earthquake, hurricane and other geohazard damage.
Ticks are a problem for geologists in some areas. Learn to recognize and avoid them.
Spatter Cones are small, steep, volcanic cones built of welded basaltic lava.
Where Are the Canary Islands? Off the northwest coast of Africa, 60 miles west of Morocco.
Morganite is an orange to pink gemstone, a variety of beryl, that is growing rapidly in popularity.
Blue Flames and the largest highly acidic lake in the world at Kawah Ijen Volcano.
Rare Earths - Special materials used in electronics, defense, medical & many other products.
Fire Opal is a transparent to translucent opal with a yellow, orange or red background color.
Hawaii*s Next Island could be growing in the Pacific Ocean right now. Its name is Lo*ihi.
Tallest Tsunami - A wave with a run-up height of 1720 feet occurred in Lituya Bay, Alaska.
Solar System Volcanoes - Earth is not the only location of volcanic activity.
Cinnabar - the only important ore of mercury. Used in pigments until its toxicity was realized.
How did the Hawaiian Islands Form? The power of a moving plate over a stationary hot spot.
Largest Hurricanes Are they determined by wind speed, value of damage, most deaths?
Talc is a soft mineral used in cosmetics, paper, paint, ceramics and many other products.
Topo Maps - The DeLorme Atlas is an entire state of topo maps in one convenient book.
Waterproof Paper - Don't take chances with your field notes and maps. Use waterproof paper.
Field Courses - Over 80 field courses for undergraduate geology students.
Chalk is a variety of limestone formed from fine-grained marine sediment known as ooze.
Tanzanite was unknown until a few decades ago but it has erupted into wide popularity.
Ruby and Sapphire are the 2nd and 3rd most popular colored stones in the United States.
Novarupta - The most powerful volcanic eruption of the 20th century occurred in the U.S.A.
Storm Surge can be the most damaging and deadly aspect of a hurricane.
Cinder Cones are the smallest, simplest, and most common type of volcano.
Coquina - A porous limestone composed almost entirely of fossil debris.
Utica Shale is a major source of oil, natural gas and natural gas liquids in PA, OH and WV.
Coal Through a Microscope - Coal is more than a black rock. It is THE most interesting rock.
Hand Lens A 10-power folding magnifier in a metal case. A frequently used lab and field tool.
The Science of Fireworks Learn how the colors and shapes are created.
The Unsung Mineral Hero - and the commodity upon which almost everything is built.
Debris Flows are moving masses of loose mud, sand, soil, rock and water.
Helium is a byproduct of the natural gas industry. Its most important use is in MRI.
Largest Volcano - That title is shared by Tamu Massif, Mauna Kea and Ojos del Salado.
Mount Vesuvius - geology, history, maps, facts and more about the Vesuvius eruptions.
California Earthquake Maps - A collection of isoseismal maps for earthquakes in California.
Ilmenite - The primary ore of titanium and source of most titanium dioxide.
Mineraloids are amorphous naturally-occurring inorganic solids that lack crystallinity.
Rocks on Mars Many of the rocks found on Mars are not very different from Earth rocks.