Minerals & Rocks Chapter 5 Lesson 1 Pg. 226-236

What are minerals? Mineral- a solid natural material made from nonliving substances in the ground Minerals are made of elements Some minerals are made of a single element Other minerals are made of two or more elements Minerals are found in nature Hematite is a mineral that contains iron

Properties of minerals The color of a mineral is the color of the surface of the mineral Streak is the color of the powder left when the mineral is rubbed on a rough surface Luster is the way a mineral reflects light from its surface Hardness is a measure of how well a mineral resists scratching A hard minerals resists scratching better than a soft miner. The Mohs’ Hardness Scale ranks minerals from softest (1) to hardness (10)

What are the shapes of minerals? As minerals form, the elements they are composed of form patterns. Those patterns cause minerals to form geometric shapes called crystals A crystal is a solid whose shape forms a fixed pattern Topaz, Mica, Amethyst, are crystals Some minerals are also called gems, such as emeralds A gem is a mineral that is rare, beautiful, usually transparent, and shines in light. They are used in jewelry

Crystals & Gems Topaz Amethyst Emerald Mica

What is the rock cycle? Nothing on Earth stays the same: air, water, land, and living things all change over time. The same is true of rocks A rock is a solid object made naturally in Earth’s crust and contains one or more minerals Most rocks are made of mixtures of materials Scientist classify rocks into three types based on the way they are formed: sedimentary, igneous, and metamorphic

What is the rock cycle? The pressure of gravity compacts, or squeezes sediments together and makes the minerals stick together. The rock that forms from sediments is called a Sedimentary Rock When sedimentary rocks are pushed underneath Earth’s crust, heat and pressure can melt them into magma. An igneous rock forms as the lava cools and hardens As time passes, sedimentary and igneous rocks can be buried deep beneath Earth’s surface. The weight of the rock above them causes intense pressure. A metamorphic rock is a rock that forms when sedimentary and igneous rocks change under heat and pressure Change from one type of rock to another is caused by changes in conditions on and underneath Earth’s surface. The changing of rocks over time from one to another is called the rock cycle

Rock Cycle

What are igneous and sedimentary rocks Igneous rocks that form from magma inside Earth are called intrusive (Granite) Granite is used as building material Igneous rocks that form from lava ON Earth’s surface is called an extrusive (Obsidian-used to make sharp tools and weapons) Pumice is used for grinding or polishing Some sedimentary rocks contain minerals that were once dissolved in water Almost all fossils are found in sedimentary rock Often used in buildings Limestone and sandstone are two types of sedimentary rocks that are used to construct buildings, make statues

What are metamorphic rocks Heat and pressure may even change one of the minerals in the rock into another mineral Limestone changes into marble under heat and pressure Slate is a type of metamorphic rock in which the minerals are tightly packed together Marble is a shiny metamorphic rock that contains minerals that give it brilliant colors