1. Rock Cycle and Types of Rocks

2. Terms to Know Rock: a mixture of naturally occurring minerals
Mineral: any naturally occurring inorganic substance
Crystal: many minerals form regular-shaped solids with flat surfaces
Metal: a solid material that is typically hard, shiny, malleable, and ductile, with good electrical and thermal conductivity (e.g., iron, gold, silver, copper, and aluminum, and alloys such as brass and steel).

3. Igneous Rocks Igneous Rock is formed when magma cools and hardens.
Magma that erupts onto the surface is called lava.
Granite
Basalt
Pumice
Gabbro
Obsidian

4. Crystals in Igneous Rocks
When magma cools slowly underground the crystals are large enough to see.
When it cools quickly on the surface, the crystals are very small and you would need a magnifier or a microscope to see them.
Sometimes, when the magma cools very quickly, it forms a kind of black glass that you cannot see through.

5. Sedimentary Rocks
Sedimentary Rock forms from particles, called sediment, that are worn off other rocks. The sediment gets turned into rock by being buried and compacted by pressure from the weight above it.
Conglomerate
Sandstone
Shale
Limestone

6. The sediments that form into sedimentary rocks are sand, silt, and clay.
Sand has the largest particles while clay has the smallest.
These rocks often contain fossils.

7. Metamorphic Rocks
Metamorphic Rock is rock that has been transformed by great heat or pressure. It is buried very deep in the earth's crust and sometimes happens when mountains are being made or two plates are pushing against each other.
Gneiss
Schist
Slate
Marble

8. Weathering, Erosion, Deposition
Rock Cycle
Magma
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks
Melting
Cools and hardens
Weathering, Erosion, Deposition
Heat and pressure

9. Gemstones
Rare, beautiful minerals, usually colourful and polished until they are clear and shiny

10. Things That Look Like Rocks But Aren’t
Beach Glass: bits of glass smoothed down by water
Brick Pebble: a piece of man- made brick smoothed down
Petrified Wood: a fossil that forms when plants are buried by sediment and protected from decay by oxygen and organisms. Then, groundwater rich in dissolved solids flows through the sediment replacing the original plant material with different minerals.

11. Can you identify the rocks?
k_key.htm#gneiss