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Earth Materials Scavenger Hunt Activity

Earth Materials Under Your Roof!

This activity can be also be found in the 2020 AGI Earth Science Week calendar (October).

This image shows a calendar of October 2020, the words Earth Science Week, and AGI contact info.
This image shows a 2020 calendar, highlighting Earth Science Week, an annual event during the second week of October to raise awareness about the Earth Sciences.

Have you ever wondered where everyday items your home or classroom come from? Did you know that many things are made from Earth materials that are mined? Earth materials include minerals, sediments, rocks, ores, and petroleum products. They form over very long time periods and are not alive.

Minerals are naturally-occurring, inorganic (meaning not from living things) solids with distinct physical properties and chemical compositions (or a range of compositions). They are the building blocks of rocks. Examples: quartz, feldspar, gypsum, talc, diamond.

Sediments are loose, unconsolidated particles of rock. Examples, from small to large: clay, silt, sand, gravel. Sand and gravel are commonly used in concrete and other construction materials. Clay minerals are commonly used in ceramics and many other materials.

Rocks are made of one or more minerals and are classified by how they form. Igneous rocks form when molten rock (lava or magma) cools and solidifies. Sedimentary rocks are made up of particles of other rocks (sediments). Metamorphic rocks are rocks that have been changed by high heat or pressure. For a brief review of rocks and minerals, visit week 12 of the USGS Learn From Home site.

Ores are bulk rock sources that contain valuable metals or other  materials. They can be processed (using heat or other methods) to extract metals and other minerals.

Petroleum products are naturally-occurring hydrocarbons that form when tiny marine organisms die, sink to the bottom of the ocean, mix with sediments, and are exposed to heat and pressure over millions of years. They are also known as fossil fuels. Petroleum products are manufactured to make flexible polymers (long-chain molecules) known as plastic.

Mining is the process of removing, or extracting, Earth materials. Some mining types include underground mining, surface (open-pit) mining, and placer mining.

What can you find around you that you think may have been mined? This activity can be done independently or in small teams. Think about the questions below, then see what you can find! Want to show us what you found? Tag us on social media @USGS_YES. Note: we can only see public accounts. If you'd like to share what you found but aren't on social media, you can e-mail us at Happy hunting!


Go on a scavenger hunt!

  1. Look around your home or classroom for items that you think may have come from mined materials.
  2. Make a pile or list of what you found. If you'd like to keep track of your guesses, you can use this worksheet.
  3. Some items are made up of more than one Earth material. See the example below about an ordinary pencil, which contains three different examples of materials that had to be mined.
  4. What did you find? What did you learn? This worksheet key shares some examples of Earth Materials that you may have found on your scavenger hunt. Additional details about Earth Materials can be found on the USGS National Mineral Information Center’s Minerals Yearbook – Metals and Minerals
  5. Stay curious! Lots of things we use every day formed through geological processes over millions of years - even aluminum foil!


Example of one thing you may find: A pencil contains three examples of Earth materials: graphite and clays (commonly called pencil ‘lead’ but does not contain actual lead (Pb).

Graphite-bearing schist, A microscopic image of clay particles (dickite), Bauxite
(USGS, Public domain.)

Graphite: A ‘core’ of the mineral graphite makes up the writing material of a pencil and is surrounded by a tube of wood that can be sharpened into a point. Graphite is a very soft mineral that rubs off easily into paper and is the crystalline form of carbon. It occurs naturally in metamorphic rocks such as marble, schist, and gneiss. Photo: Graphite-bearing schist (USGS). Learn more about graphite here.

Clays: Clay minerals (such as bentonite or kaolin) are used in pencils to help the graphite stick together. Clay minerals are composed of thin sheets of Al, Si, and O and form in the presence of water. Photo: A microscopic image of clay particles (dickite)/USGS. Learn more about clay minerals here.

Aluminum Ore (Bauxite): A small piece (ferrule) of aluminum metal is used at the end of a pencil to secure the eraser. Bauxite is a heterogeneous (mixed) material made up of aluminum hydroxide minerals, plus various types of silica, iron oxides, titanium, aluminosilicate, and other impurities. Photo: Bauxite, USGS. Learn more about aluminum here.

Common Earth materials found in everyday household items: Limestone, gypsum, clay minerals, silica, nickel, aluminum, zinc, iron ore, steel (metallic iron from iron ore plus carbon), micas, petroleum products, sand and gravel, gold, graphite, selenium, vermiculite, and more.

Where on Earth can these minerals be found? What do you notice about the global distribution of minerals? The interactive map below can be found here. Did you know that the United States relies on these countries for 50 or more certain minerals?

Minerals in a mobile device
More than one-half of all components in a mobile device are made from mined and semiprocessed materials (mineral commodities)! 

What minerals are in my cell phone? Mobile devices contain many different minerals, elements, and metals, each of which have to be mined. Some examples of the minerals used include sphalerite (a zinc sulfide mineral that is a source of the element Indium used in the screen's coating), chalcopyrite (a copper, iron, sulfide mineral that is mined for the copper, which consucts electricity and heat, and arsenopyrite (an iron, arsenic, sulfide mineral that is mined for the arsenic, which is used in radio frequency and power amplification), and more! The USGS General Information Product, 'A World of Minerals in your Mobile Device', can be downloaded here.


What mineral commodities are in Navy SEAL gear? At least 23 nonfuel mineral commodoties are also needed to produce several of the components used in Navy SEAL gear, including the elements gallium (Ga), Terbium (Tb), and vanadium (V). The USGS General Information Product, 'Globally sourced mineral commodities used in U.S. Navy SEAL gear—An illustration of U.S. net import reliance,' can be downloaded here.



Want more links about USGS Minerals and Earth Resources? Major Mineral Deposits of the World (interactive map)Do we take minerals for granted? What is hydraulic fracturing, or “fracking”? 2020 Mineral Commodity Summaries2020 Report Highlights the Importance of Mining Minerals for U.S. Economy and National SecurityThe Life Cycle of a Mineral Deposit: A Teacher’s Guide for Hands-on Mineral Education Activities, 2005USGS Fact Sheet: Obsolete Computers, “Gold-Mine or High-Tech Trash? Resource Recovery from Recycling, 2001


Want to know more about each day of Earth Science Week? VIsit this page to learn more about this year’s Earth Science Week activities at USGS and AGI.