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Minerals

Minerals

The different layers of the Earth are made up of minerals and rocks. Minerals are materials that happen naturally. They have a fixed chemical formula and an orderly crystalline structure.
Quarzt Feldspar Gypsum Talc
QUARTZ FELDSPAR GYPSUM TALC
Orthoclase Mica Magnetite
ORTHOCLASE CORUNDUM MICA MAGNETITE

Properties of minerals

Minerals are classified depending on their composition but there are some properties that may be useful to identify minerals. Some are: colour, streak, lustre, crystal habit, hardness, cleavage, tenacity and magnetism.
ScratchScratch test. Jimmie. Flickr. (CC-BY) STREAK:  It is the colour of the powder remaining when a mineral is scratched. LUSTRE: It is the description of how light reacts on the surface of the mineral, for example, transparent, metallic, pearly... CRYSTAL HABIT: It refers to the general external shape of a mineral, for example, cubic, octahedral...
HARDNESS: It is the resistance of a mineral to be scratched by another mineral. CLEAVAGE: It is the way a mineral breaks through its weaker part. TENACITY: It is the reaction of a mineral to situations such as breaking or bending. Different forms of tenacity are: malleability, flexibility, ductility, frailty, etc. MAGNETISM: It is the power of a mineral to attract or push away iron or steel elements.

Activity 1 and 2

1. Complete the words.
FELD G UM CLEA NDUM MAGNE
ORT LASE NETITE STRE TRE STAL HABIT
QU Z TENA HARD TA MI
2. Separate the words in the previous exercice into two groups, one including the minerals and the other including the properties of the minerlas

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Activity 3

3. Read these statements and write which property they represent.
1. It is olive green though it may alter to reddish.
Beryl
Three varieties of beryl (left to right): morganite, aquamarine and emerald. Chris Ralph. Wikipedia. (Public Domain).
2. It shows isolated tetrahedra.
3. It is vitreous and sometimes opaque.
4. We can flat silver by pounding with a hammer.
5. Talc can be scratched with your nails.
6. When you scratch gold, it leaves yellow powder.
7. Calcite shows perfect rhombohedrals when it breaks.

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Activity 4

Here you have the definition of the properties of minerals. Listen and choose the words that are missing.
STREAK:  It is the colour of the remaining when a mineral is scratched. LUSTRE: It is the description of how light on the surface of the mineral, for example, transparent, metallic, pearly... CRYSTAL HABIT: It refers to the general external of a mineral, for example, cubic, octahedral...

HARDNESS: It is the of a mineral to be scratched by another mineral.

CLEAVAGE: It is the way a mineral through its part.

TENACITY: It is the reaction of a mineral to situations such as breaking or bending. Different forms of tenacity are: , flexibility, , frailty, etc.

MAGNETISM: It is the power of a mineral to or push away iron or steel elements.

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Extra activities

Topaz
             Red topaz crystal taken at the National History Museum, London          .Aram Dulyam. Wikimedia. (Public Domain)

1. Listen to some words used to talk about the properties of minerals. Search the Internet to find out what they refer to.

Pearly

Ductility

Malleability
Failtry
Octahedral

Teamwork2. In groups of three search the Internet to find out if the following sentences are true or false and explain why. Prepare to tell the rest of the students.

1. Siderite is attracted by magnetite.

2. Quartz, orthoclase and calcite are silicate minerals.

3. Diamonds are made up of carbon.

4. Gypsum has a salty taste.

5. Ruby and sapphire are varieties of corundum.

6. Topaz and olivine show an orthorhombic crystal system.

7. Quartz is harder than topaz.

Projects

MINERAL FAIR
Group A Group B Group c
Have a look at this link. You can see Mohn's hardness list. Create a poster to show the rest of students which minerals are in the list and why they are in the list. If possible use photos of the minerals and explain who Mohs was.

Create a fact file sheet including a photo of the minerals and the properties you have seen in this unit. Use the minerals in the first exercise of this unit and add other common minerals in Galicia.

If it is possible show real minerals too.

Organize the information from the other groups so that all students in the school can see it properly.

Group a: Make a poster with the use of minerals in our daily life.

Group b: Make a poster informing how to handle minerals safely.
When the posters and fact sheets and real minerals are ready, group 3 member will organize the information. Students should be able to explain other students visiting the Mineral Fair the aspects they have worked on.