Name ______Date ______Per ______

MINERALS

DEFINITION OF MINERAL:

Minerals make up rocks, and all minerals...

1.  Are ______, and have a definite ______

• each mineral is always in the same crystal system

examples:

pyrite always forms ______crystals

quartz always forms ______crystals

2. Have a unique ______; they are

either ______or ______

• most are compounds

• each mineral always has the same composition

examples:

pyrite is always ______

quartz is always ______

3. All are ______

• not living (and never were)

4. All are ______(not man-made)

MINERAL IDENTIFICATION PROPERTIES

Color

• ______:

• some minerals (like quartz or fluorite) come in ______

due to ______and...

• many different minerals can be ______

Cleavage

• when a mineral ______

Types of cleavage:

• ______: 1 direction only; splits like pages in a book

• ______: 3 directions at 90°; tends to form cubes

• ______: 3 directions not at 90°; forms rhomboids

• 2 directions at various angles

• 4 directions at various angles (rare) Flourite

Fracture

• when a mineral ______

• many minerals show cleavage in 1 or more directions, and fracture in all other directions

Types of fracture:

• ______: no obvious pattern

• most common type of fracture

• ______: often shows this pattern:

• ______: breaks into slender fragment

Luster

• the way a mineral______

• look for the ______surface on a sample to classify

Types of luster:

• ______(aka vitreous); reflects like glass, but may not be transparent

• ______; shines like metal

• ______; chalky or powdery looking

• ______; like mother-of-pearl in some sea shells

• ______; like wax

• ______; like hardened tree sap

Density

• ______; how heavy a sample is for its size

• expressed in ______

Specific Gravity

• density of sample ÷ ______1 g/mL)

• S.G. of a sample has same value as its density in g/mL, but uses no ______

Streak

• ______

• usually a porcelain streak plate is used

Hardness

• the ability of a mineral to ______

• ______scale (1 to 10) is used as a reference

1 = ______(softest), 10 = ______(hardest)

• an 8 is not 4 times harder than a 2 - it’s just a lot harder

Moh’s Hardness Scale

1 ______

2 ______

3 ______

4 ______

5 ______

6 ______

7 ______

8 ______

9 ______

10 ______

• always start with ______(H = 5.5), to narrow down choices

• some other common substances can also be used:

______(2.5)

______(3.5)

______(5.5)

______(6.5)

• be sure “scratch” doesn't wipe off; it may be just a ______

Crystal Structure

• sometimes crystal shapes can be seen in sample

Special Properties

• helpful because not many minerals have them

______glows a different color under UV light

______glows after UV light is off

______double image seen through a clear sample ex: clear samples of calcite

Reacts with Acid ex: calcite forms bubbles of ______

Smell ex: streak of sphalerite smells like ______

Taste (dangerous!) ex: ______tastes like table salt (it is table salt)

Flammability ex: ______

Radioactivity

• contains elements that are ______(nuclear fission)

Malleability

• the ability of a mineral to be ______

Ductility

• the ability of a mineral to ______

Magnetism

• only common magnetic mineral is ______

Practice:

Name of mineral / Color / Cleavage or Fracture / Luster / Streak / Hardness / Special Properties

IMPORTANCE OF MINERALS

Ores - Minerals mined for ______

2 Basic Types:

1. ______

• contain extractable metals

examples:

______(ore of lead)

______(ore of iron)

______(ore of iron

______(ore of zinc)

2. ______

• mined for materials other than metals

examples:

______(road fill, construction, medicines)

______(abrasives)

______(plaster)

______(sand, glass, silicon)

______(baby powder)

______- lustrous, colorful samples of various minerals

• usually minerals are ______

ex: most diamonds are used in cutting tools

GROUPS OF MINERALS

1.  ______- contain Si and O

• over 92% of all minerals

• different silicates have other elements too

ex:______(the most common mineral)

quartz

micas

talc

2. ______- don't contain both Si & O

• types of nonsilicates

• native ______

ex: copper, gold, iron, sulfur, carbon

• sulfides (contain ___);

ex: pyrite,( ______) and sphalerite, (______)

• sulfates (contain ______); ex: gypsum, (______)

• carbonates (contain ______); ex: calcite,( ______)

• oxides (contain ____ ) ex: hematite, (______) corundum, (______)

• halides (contain ______) ex: fluorite, ______halite, ______

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