Magnificent Minerals By Satchel Harris

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1 Magnificent Minerals By Satchel Harris

2 Table of Contents What Is a Mineral?... 1 Cool ol Crystals... 3 Glorious Gemstones.. 7 Mischievous Myths about Minerals... 9 Minerals are Resources Glossary.. 13

3 What Is a Mineral? Have you ever looked at a crystal and wondered about it? Where did it come from? Why is one crystal red and another crystal blue? Did you know that a crystal is a mineral? This book will teach you what a mineral is, how you can identify them, and what we use them for. Minerals are the building blocks of rocks. An example is granite. Its minerals are quartz, feldspar and mica. Minerals come in different colors, shapes, and sizes 1

4 The definition of mineral is: An inorganic solid that has a regular arrangement of atoms and molecules. Every mineral has a unique combination of elements. There are over 2,500 types of minerals, but most of them are rare. Less than 100 minerals are common. Most minerals have more than one element. An example is wulfenite (PbMoO 4 ). It is made of lead molybdenum oxide. But some minerals are made of only one element. Two of these minerals are graphite and diamond. They are made of pure carbon, absolutely nothing else. This picture shows the red variety of the mineral wulfenite. Some minerals aren t even real minerals! An example is opal. Opal is hardened silica gel. Some minerals have a lot of variety. A great example is beryl. Beryl is a mineral composed of beryllium aluminum cyclosilicate. Emerald is a variety of deep 2

5 This is a picture of bixbite from the rock collection of Satchel Harris. green beryl, while aquamarine is blue/blue- green. Heliodor is yellow or yellow green beryl, and morganite is pink beryl. The rarest variety, bixbite, is a deep red. Bixbite only comes from two locations in Utah. It is so rare that it is one of the rarest minerals on the planet. Cool ol Crystals A crystal is a mineral that has a geometric and symmetrical composition. The shape of a crystal is what makes it different from another. For example, halite forms cubes and quartz forms hexagons. Garnets have 12 or 24 sides. When conditions are right, crystals will form spectacular shapes. These are the ones that cost the most money. 3

6 On the left is the atom arrangement of a diamond. On the right is the atom arrangement of graphite. The better the atoms are arranged in a crystal, the harder it will be. Mineralogists also identify crystals by their color, hardness, cleavage and other unique properties. One of the easiest identification techniques is using color. Minerals such as malachite and azurite all have very Garnet is derived from the Latin word for pomegranate. 4

7 Hematite is a silvery gray mineral that has a red streak. The red color comes from iron. distinctive colors. Malachite is a deep green, while azurite is azure blue. Ruby is the very bold magenta color of corundum. There is also something called streak. Streak is the color a mineral makes when it is rubbed against a special tile. For example, the streak of pyrite is yellow because it is a sulfide. The streak of some minerals is their color. Malachite and azurite are two of these minerals. Scientists identify minerals by their hardness too. Fredrick Mohs was a German mineralogist who identified minerals by their Diamond is by far the hardest crystal. It is almost four times as hard as corundum (ruby/sapphire). 5

8 hardness. He was so into the idea, in fact, that he came up with a genius idea. He invented a scale called the Mohs scale. It rates the hardness of minerals on a scale of 1 to 10. Hardness 2 and under can be scratched with your fingernail. Hardness 3 and under can be scratched with a penny. Hardness 4 and under can be scratched with a penknife blade. Hardness 5 and under can be scratched with a shard of glass. Hardness 6 can be scratched with a cheese grater and Hardness 7 can be scratched with a counter tile. Hardness 8 through 10 can only be scratched with a special tool. The tool is a very sharp scalpel that sometimes has a diamond blade. This picture shows the hardness of minerals according to Mohs Scale. 6

9 Another way that geologists identify minerals is by their cleavage. Cleavage is the way a crystal breaks. For example, the mineral mica is very easy to identify because of its cleavage. Mica can be peeled off the matrix in very thin sheets. Mica also has very bold colors such as black, brassy yellow and brown. This is a picture of mica and its cleavage. The final way that scientists identify minerals is by unique properties. Each mineral has a unique personality, like sulfur smells like rotten eggs, halite tastes salty, calcite reacts with acid and magnetite can attract metal objects. Glorious Gemstones Gemstones are a special group of minerals with unusual properties. Crystals of a gemstone bounce and bend light. A person who finds a 7

10 gemstone might not recognize it because it looks like an ordinary rock. For a gemstone to be beautiful, it has to be cut, faceted and polished. The person who does this is called a lapidary. The properties of a gemstone are rarity, durability and beauty. One of the rarest gemstones is benitoite because it only comes from three locations in the world. Beryl is one of the most durable minerals second only to corundum and The gemstone topaz is found in Utah at Topaz Mountain. The Pink Star Diamond was mined in 1999 in South Africa. It was sold for $83 million, more than any other diamond or gem ever sold. diamond. How beautiful a gemstone is depends on your point of view. Many people think diamonds are pretty while some people, like me, think tourmaline is pretty and colorful. 8

11 Common gemstones are sometimes not gem quality. For example corundum sometimes occurs as an ordinary mineral called emery. Sometimes corundum occurs as beautiful, sparkling sapphires. Mischievous Myths about Minerals Since ancient times, people have believed that crystals have special powers. An example is crystal balls. People used crystal balls to predict the future. Light shines through the crystal ball and a mist appears. People say they see things in the mist. People used to believe that emeralds blinded snakes. In ancient Persia people believed that the world was on top of a giant sapphire. They thought the reflection of it was what made the 9

12 sky blue. Egyptians believed that colored gemstones could heal people. And Native Americans thought that if you attached a piece of turquoise to a gun or a bow it would give them perfect aim. Minerals are also important as birthstones. Every month has a different gem. The gems stand for different qualities in a person. For example, garnet is the January birthstone and it represents constancy. Emerald is the May birthstone and it represents love and success. Birds may have a tiny magnetic crystal in their brain that allows them to locate the earth s magnetic field. 10

13 Minerals are Resources Minerals are very important resources in our world. Minerals such as copper, aluminum, nickel, lead, iron and zinc are all mined from rocks in the ground. We all use mineral resources every day. There are two big problems with using mineral resources. One is that mining causes big problems. Underground mines are dangerous and they can even collapse. Surface mines can strip away the earth and can pollute streams and cause mudflows and landslides. Another problem with using mineral resources is they are not renewable. That means that someday we will run out. We can stop this by recycling. Kennecott s Bingham Copper Mine is the largest mine in the United States. 11

14 Things that can be recycled include aluminum cans, plumbing pipes, old cars, and anything else that is made of minerals. Recycling is a good thing and it helps the community, which is every living thing. If the Bingham Copper Mine in Utah was a stadium, it could fit nine million people. That s bigger than New York City! Remember to recycle!!! EVERYONE! 12

15 Glossary cleavage- the way a mineral splits apart crystal- a mineral that has a certain arrangement of atoms and molecules inorganic- non- living lapidary- someone who cuts and polishes gemstones matrix- what a mineral is embedded in mineral- an inorganic solid with a regular arrangement of atoms and molecules streak- the color a mineral makes when it is rubbed against a special tile surface mines- a mine that is not underground 13