Rocks and Minerals by UTH Rocks and Minerals by UTH    

Lesson 10: Physical Properties: Fracture

Directions

Study the lesson for one week.

Over the week:

• Read the lesson.
• Review the synopsis.
• Recite aloud the vocabulary words and their definitions.
• Study the rock and mineral of the week.
• Complete the enrichment activities.
• Study the review questions.

Synopsis

Rocks and minerals may be identified by one or more of their physical properties. One identifying physical property of rocks and minerals is fracture. Fracture is the tendency of a mineral to break into irregular pieces. There are different types of fracture, including crumbly, splintery, uneven, conchoidal, and hackly.

Vocabulary

Physical Property: Characteristics of matter not involving a change in chemical composition.
Fracture: The tendency of a mineral to break into irregular pieces.
Ore: Rock or other material that contains valuable or useful materials.
Magnet: A piece of material that attracts some metals by magnetism.

Rock or Mineral of the Week

Overview

• Magnetite is a silvery gray-black iron (Fe) oxide (O) mineral.
• Magnetite is mined as an ore for the iron (Fe) it contains.
• Magnetite, hinted at by its name, has magnetic properties.
• Magnetite is both attracted to a magnet and can become magnetized itself.

Physical Characteristics

• Color: Silvery Gray to Black
• Hardness: 5-6.5
• Luster: Metallic
• Cleavage: None
• Streak: Black
• Tenacity: Brittle

Locations

• Hong Kong, the United States, New Zealand, and other places

Interesting Facts

• Some magnetite, called lodestone, is magnetized and can attract metal.
• Finding naturally occurring lodestone is how our ancestors discovered the property of magnetism.
• Magnetite is often found in the form of a black sand.
• See a black sand containing magnetite, hematite, and gold.

Enrichment

Activity 1: Narrate the Lesson

• After reading or listening to the lesson, narrate the lesson aloud using your own words.

Activity 2: Can You Find It?

Find the following elements on the periodic table:

• Iron (Fe)
• Oxygen (O)
• In which group and period is Iron (Fe)?

Activity 3: Map the Lesson

• Magnetite is found on the western side of the northern island of New Zealand.
• Find New Zealand and its northern island on the map of Australia and New Zealand.

Activity 4: Take a Nature Walk

• Embark on a nature walk.
• Collect one rock or mineral specimen.
• Use the gathered specimen to create the field book entry.

Activity 5: Complete a Field Book Entry   

After your nature walk, complete page 6 in 'Fifth Grade Science Rocks and Minerals Notebook Pages.'

Review

Question 1

Is fracture a physical property or a chemical property?

1 / 5

Answer 1

Fracture is a physical property, for it does not involve a change in chemical composition.

1 / 5

Question 2

Describe something about lodestone (Fe3O4).

2 / 5

Answer 2

Lodestone is a naturally magnetized form of magnetite.

2 / 5

Question 3

Is magnetite (Fe3O4) a compound?

3 / 5

Answer 3

Yes, magnetite (Fe3O4) is a compound containing more than one type of element.

3 / 5

Question 4

Why is magnetite (Fe3O4) considered an ore?

4 / 5

Answer 4

Magnetite (Fe3O4) contains valuable iron (Fe), so it is mined as an ore for profit.

4 / 5

Question 5

How many different elements does magnetite (Fe3O4) contain?

5 / 5

Answer 5

Magnetite (Fe3O4) contains two types of elements - Iron (Fe) and Oxygen (O).

5 / 5

❮ ❯

1. Is fracture a physical property or a chemical property? Fracture is a physical property, for it does not involve a change in chemical composition.
2. Describe something about lodestone (Fe3O4). Lodestone is a naturally magnetized form of magnetite.
3. Is magnetite (Fe3O4) a compound? Yes, magnetite (Fe3O4) is a compound containing more than one type of element.
4. Why is magnetite (Fe3O4) considered an ore? Magnetite (Fe3O4) contains valuable iron (Fe), so it is mined as an ore for profit.
5. How many different elements does magnetite (Fe3O4) contain? Magnetite (Fe3O4) contains two types of elements - Iron (Fe) and Oxygen (O).

References

'Magnetite.' Wikipedia. en.wikipedia.org/wiki/Painite. n.p.

Cited Physical Properties. Geology.com. geology.com/rocks. n.p.