MANY MINERALS Minerals are found all over the world The ground beneath your feet has minerals in it Minerals are also in the water you drink and the food you eat Minerals are in Earth’s rocks sands and soils Minerals can be found on Earth’s surface They are also deep underground There are several thousand different minerals on Earth Scientists who study minerals are called mineralogists Mineralogists freqently discover new minerals You Many minerals can be found in mines deep underground 4
probably know some types of minerals Metals like gold silver and copper are minerals Precious gems like diamonds and rubies are also minerals Even the salt you use at dinner is a mineral Some minerals are not well known but they are an important part of many objects on Earth For example lithium is used to make batteries and mica is used in paints Minerals come in many shapes sizes and colors Some minerals can be cut and polished to form beautiful stones These gems are often used in jewelry Vocabulary 5
WHAT ARE MINERALS Minerals are solid substances that occur naturally They are not made by people though people can make artificial versions of some minerals Minerals are also inorganic That means they do not come from any living thing Minerals are made from one or more elements An element is a substance that is made from a single type of atom Each mineral has a specific chemical composition That means that the elements in a particular mineral are always the same Most minerals are made of some combination of the following eight elements oxygen silicon aluminum iron magnesium calcium potassium and sodium The mineral quartz has a crystal structure 6
Different crystals have different structures and geometric shapes Most minerals form in a crystal structure A crystal is a solid object with flat faces sharp edges and angles The atoms of a crystal are organized in a regular repeating pattern Some people think that rocks and minerals are the same thing but they are not A mineral has a specific chemical composition A rock can contain several different minerals that are mixed up together Rocks therefore do not have a specific chemical composition Volcanic glass is a naturally formed solid It does not have a specific chemical composition or crystal structure Is it a mineral Why or why not Think About It AB C gypsum wulfenite halite 7
