Geology
Lab- Crystal Formation
Names__________________________
__________________________
Solids have a regular, orderly arrangement of their internal atoms. This is known as the crystalline
structure or crystal form. If the mineral is able to grow in an unrestricted space, it may develop the
external shape of the crystalline structure, a crystal. When found, a well-formed crystal structure tells
us much about the internal structure and greatly aids to the identification of the mineral.
Objective:
To recognize different crystal forms and relate them to the six basic crystal systems.
Materials:
2 different dry chemicals
1 glass Beaker
2 Paper Clips
Water-based marker
2 test tubes
Water
Hand Lens
2 Copper nails
Hot Plate
Goggles
Procedure:
1. Please place all computer equipment, or paper away from the lab station.
2. With the water-based marker, write your group initials on the 30 ml test tube and the chemical
being used in the test tube.
3. Fill one 30 ml test tube with water. Pour this water into a glass beaker and heat for
approximately 3 minutes.
4. When the water is very hot (not boiling) add a very small amount of the dry chemicals to the
water. Stir with the nail until no more of the chemical will dissolve. You want to dissolve as
much of the dry chemical into the water as possible. If grains appear at the bottom of the
beaker, you have added enough of the chemical.
5. Using a damp paper towel , carefully pick the beaker up and pour the solution into one test tube.
6. Tie a 5-6 inch piece of string to the nail and drop it into the solution. Tie the other end of the
thread to a paper clip that will balance on the top of the test tube.
7. Adjust the length of the string so that the nail does not quite touch the bottom of the test tube
and so that the string is straight and not wrinkled.
8. Place the test tube in one of the racks where it will not be disturbed. Check to be sure you have
marked the test tube with your initials and for the identification of the chemical used. Wait 3-4
days for the crystals to develop fully.
9. Repeat the procedure with another dry chemical, WORK SAFELY!!
10. After both test tubes are set in a safe location, open the crystal growing experiment and follow
the manual to grow additional crystals.
Name ____________________ Partner name _________________________
Crystal Construction Lab
Please construct each crystal and sketch the model below, use colored pencils to show different
types of element. Please label each type of element. Then go to the following links to answers
relevant questions about each crystal.
1. Graphite Crystal
Graphite Link: http://en.wikipedia.org/wiki/Graphite
a. What rock is graphite most closely related to? ___________________
b. What is graphite used in? _____________________________________
c. What is the crystal shape (system) of graphite? _________________________
d. List one other interesting fact about graphite:
2. Diamond Crystal
Graphite Link: http://en.wikipedia.org/wiki/Diamond
a. What can make a diamond yellow or blue in color? _______________________
_____________________________
b. How long does a diamond take to form in the Earth?__________________________
c. What is the crystal shape (system) of a diamond? _________________________
d. List one other interesting fact about diamonds:
3. NaCl (Halite) Crystal
Graphite Link: http://en.wikipedia.org/wiki/Halite
a. How is halite created? ___________________________________________________
b. How is halite used to make ice cream?______________________________________
c. What is the crystal shape (system) of a halite? _________________________
d. List one other interesting fact about halite:
Conclusion Questions (page 166 of your textbook may be helpful)
Review Questions
1. Cleavage and crystal shape are both the result of what chemical property?
2. Why is color alone not a good physical property for classifying minerals?
11. When finished, wash out the beaker, dry the beaker and return all materials to their proper
storage place.
Results:
1. Identify the name and chemical formula for the first chemical used:
_________________________________________________________________
2. Identify the name and chemical formula for the second chemical used:
_________________________________________________________________
3. What is the chemical formula for sugar? _________________
4. Please draw the sugar molecule below:
5. Why are crystals important to us?
After 5-7 days:
6. After the crystals have formed on each string, carefully remove each string from its tube and
describe the crystals.
Chemical #1 ______________________________________________________________
Chemical #2 ______________________________________________________________
7. Turn to page 166 in your textbook, which crystal systems do your think the crystal you grew,
belong to? Study the crystals with a hand lens.
Crystal #1 ________________________________________________________
Crystal #2 ________________________________________________________
Conclusion:
What does the crystal shape tell us about the internal structure of a mineral? How can the crystal
structure help us identify minerals?
____________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
DENSITY PROBLEMS (Show your work!!) Densities of some common substances Substances Density (g/cm) Air 0.0013 Gasoline 0.7 Wood (oak) 0.85 Water (ice) 0.92 Water (liquid) 1 Aluminum 2.7 Steel 7.8 Silver 10.5 Lead 11.3 Gold 19.3 1. Mass = 10.3 g Volume = 14.7 cm3 Name _______________________ Date _______________ Density = ________________________ ________________________ 2. Mass = 50 g Volume = 4.42 cm3 Density = ________________________ ________________________ 3. Mass = 15 g 4. Mass = 15 g Volume = 15 cm3 Volume = 16.3 cm3 Density = ________________________ Density = ________________________ ________________________ ________________________ 5. Mass = 5 g 6. Mass = 2 g Volume = 0.26 cm3 Volume = 0.26 cm3 Density = ________________________ Density = ________________________ ________________________ ________________________ 7. What did questions 3 and 4 have in common? How did they differ? Which question has more mass per volume? Which answer has a greater density? DENSITY PROBLEMS (continued) 8. Mass = 252 grams, length = 6 cm, width = 4 cm, height = 1 cm Volume = _________________ Density = _________________ Substance = _________________ 9. Mass = 255 g, length = 5 cm, width = 3 cm, height = 2 cm Volume = _________________ Density = _________________ 10. Mass = 3.375 kg, length = 25 cm, width = 10 cm, height = 5 cm Volume = _________________ Density = _________________ Substance = _________________ 11. A sheet of aluminum has a volume of 54 cm3. What is its mass? 12. A block of oak wood has a volume of 100 cm3. What is it max? 13. A steel plate measures 20 cm long, 8 cm wide, and 2 cm high. What is the mass of this plate? 14. A lead ball has a mass of 70 grams. What is its volume? 15. A container of water has a mass of 98.4 grams. What is its volume? 16. An ice cube measures 5 cm long, 2 cm wide, and 2 cm high. What is the mass of the ice cube? Date
Name
3-1
_
Mineral Term Game
Write the word that best fits the description on the left. When you are finished, the boxed
letters will answer the question: What represents the flowers of the mineral kingdom?
(a two-word answer).
1. Tendency of minerals to break in certain
directions
2. A mineral's resistance to being scratched
3. Number 4 on the scale of hardness
4. The ability of a mineral to hold together
5. A colorless form of mica
6. The way a mineral breaks
7. A mineral that will bend and spring back
8. Number 3 on the scale of hardness
9. The color of a thin layer of finely
powdered mineral
10. Major ore of the metal beryllium
11. Another name for olivine
12. Also known as soapstone
13. Orthoclase belongs in this group
14. How a mineral shines
@ A major element in quartz
____ 0
_
_0
_
____ 0
_
_____ 0 __
____ 0
_
_____ 0 __
___ 0
_
___ 0
_
~_O
_
___ 0_
____ 0
_
0 _
______ 0_
0
-
0
_
c
o
~
Gl
.g'"
lZl
.:
oJ:
~
Gl
.,'"
='"
"0
~
-c
'-"
Name __- - - - - - - - - - - - ­
~
1\).
3-3
Date
_
"'-"
Mineral Properties
Complete this crossword puzzle using words relating to mineral
properties.
Across
1
4. Uranium gives off radiations that can be detected with a Geiger
counter
8
(6. The breakage of a mineral so it yields definite flat surfaces
·3
~.9
.c
...e
~
~
"i
~
8:
-e
.2
..
se
4>
U
~
~
~
Q
8. A mineral that will bend and spring back
9. A mineral that can be bent without breaking and will stay bent
10. A number indicating the ratio of the weight of a mineral to that
of an equal volume of water (two words)
12. A mineral that can be drawn out into a wire
14. A mineral that can be flattened without breaking
15. A mineral that will fizz or bubble when touched with hydro­
chloric acid
17. The manner in which a mineral breaks
(19~ The ~ay ordinary light reflects from a mineral's surface
.20. The taste of halite
Down
1. Mineral particles held loosely together
(2. The color of a powdered mineral .
3. Lodestone is said to be this
5. A·mineral's resistance to scratching
7. The hue or appearance of a mineral
11. The emission of colored light rays by a substance during expo­
sure to ultraviolet light
13. The continued giving off of light rays from certain minerals
after exposure to ultraviolet light
16. A mineral that can be cut into shavings with a knife
a.,.
10
I~
Name
--------------
to http://www.classzone.com/books/earth science/terc/navigation/visualization.cfm,
",0 to chapter 5 "Atoms and Minerals" and click on the title below to answer the questions.
C'q
ubserve common objects made of minerals.
1. What common items are made from these minerals?
Halite
Quartz
- - - - - - - - - - Gypsum
_
Fluorite - - - - - - - - - - ­
Graphite
_
Gold
_
-----------
Now go to the top menu and click on "Investigations."
Again go to chapter 5 and click on the title below to answer the questions.
How Do Crystals Grow?
1. Page 1, what year was the picture of the snowflakes taken?
2. How are all of the crystals the same in the picture, how are they different?
_
3. Page 2, 'Watch a Snowflake Grow,' how does the snowflake grow?
4. Page 4, 'Crystal Growth Animations,' describe similarities shared by all crystals as they
grow?
5. Which of the two crystal growth examples, salt or pentacene are the larger crystals, how
do you know?
6. Page 5, 'Visible Crystals Reflect Molecular Structure,' what is the name of the model
what does it show?
7. Page 6, 'More Crystal Structures,' based on the models, predict the crystal shapes of
quartz and galena?
8. Page 7, 'Limited Space for Growth,' describe what happens when one growing crystal
encounters another growing crystal.
9. Page 8, 'What Controls Crystal Growth?,' what is the variable that controls how large
table salt crystals grow?
lO.Page 9, 'Simulated Crystal Growth Experiments,' describe the effect of temperature on
the growth of these crystals from a solution.
II.Describe the effect of pressure on the growth of these crystals from a solution.
.'
•
Name·
......;.
~--
lNERAL WORKSHEET
Using Physical Properties to identify minerals
.jl~·.~~:0;~'~¥l~~~~t'; :B~r~~~~~!.,
I
Sample
Color
#
White, black,
.gray, green,
yellow, blue,
red, orange,
brown, etc.
Feel
~
Streak
Color of the
• Gritty- Sandy
mineral when It's
• Powdery- Earthy scratched across
or chalky
a streak plate
• Smooth-- Glass
• Smooth & stickyWaxy
• Sharp-- Metallic
Smell
Luster
Magnetic Chemical
Hardness
Weight
Reacts to
acid (fizzes)
Yes or No
Mohs Scale
Scratched by'
Specific gravityweightgoes
from verylight (Diatomite) to
very heavy (Magnetite)
• Earthy
Attracts to
• Glassy/vitreous­
a magnet
shines likeglass
• Sour
Yes or No
• Sweet
• Earthy/chalky-dull
• Rotten egg • Metallic-looks like
• Other
metal
• Waxy/silky/pearly-has
a muted shine
1
2 Fingernail
3
.4 Penny
5 Steel (knife blade)
t:l
(.ll~.,.,
•
Name'
~
~==
lNERAL WORKSHEET
UsingPhysical Properties to identify minera1s
'-'=""'=9P'~""'~"""'.:::i';"':4!'S;::~L;;"'::::;"-"-::::;;i.:.i"::;';':";",".';'."$:. /,.,:, !,::.'>";",'i";;:··',
Sample
#
I
Color
Feel
Streak
White, black,
~
Color of the
.gray, green, • Gritty- Sandy
mineral when Ifs
yellow, blue, • Powdery- Earthy scratched across
or chalky
red, orange,
a streak plate
brown, etc. • Smooth- Glass
• Smooth & sticky Waxy
• Sharp-- Metallic
Smell
Luster
Magnetic Chemical
• Earthy
Attracts to
• Glassylvitreous­
a magnet
shines like glass
• Sour
Yes or No
• Sweet
• Earthy/chalky-dull
• Rotten egg • Metallic-looks like
metal
• Other
• Waxy/silky/pearly-has
a muted shine
Reaetsto
acid (fizzes)
Yes or No
Hardness
Weight
Mohs Scale
Scratched by.
Specific gravityweightgoes
from very light (Diatomite) to
very heavy(Magnetite)
1
2 Fingernail
3
.4 Penny
5 Steel (knife blade)
?\
not...".
Scratches Glass
Non-Metallic Light-Colered
Does not Scratch
Glass
Scratches Glass
Non-metallic Dark Color
Does not Scratch
Glass
Metallic Luster
Mineral Identification Key
White or pink, two cleavage planes
Cleavage
at nearly right angles, H-6, S-white
Glassy luster, transparent to opaque,
No Cleavage six-sided crystals, H-7, S-white
conchoidal fracture
Colorless to gray, glassy luster, three
cleavage planes at right angles,
H-2.5-3, S-white
Colorless to tinted, three cleavage
planes not at right angles, double image
when you look through it, H-3, S-white
White to green, soapy feel, one cleavage
Cleavage
plane, thin scales, H-1, S-White
White to pink to colorless, one good
cleavage plane, small pieces,
flexible, H-1-2.5, S-white
Colorless to light gray or brown,
one clevage plane, thin sheets,
H-2-2.5, S-white
Resinous, bright yellow, white streak
No Cleavage conchoidal fracture, characteristic
odor, H-1.5-2.5
Dark green, brown, or black, two
Cleavage
cleavage planes at 56 and 124
degrees, H-5-6, S-white
Black to dark brown, one cleavage
Cleavage
plane thin sheets, H-2.2-3,
S-white to gray
Reddish brown to black, metallic to
No Cleavage earthy luster, H-5.5-6.5, S-red to
red-brown
Iron black, some magnetic varieties,
H-5-6, S-black
Black to gray, greasy feel, one cleavage
plane, soft, flaky, H-1-2, S-black
Brass yellow uneven fracture, cubic
crystals, H-6-6.5, S-greenish black
Lead gray, very heavy, three cleavage
planes at right angles, H-2.5, S-lead
gray to black
Greenish to coppery yellow, duller than
pyrite, H-3.5-4
Orthoclase
Quartz
Halite
Calcite
Talc
Gypsum
Muscovite
Sulfur
Hornblende
Biotite
Hematite
Magnetite
Graphite
Pyrite
Galena
Chalcopyrite
Name
_
MODERN
Class
EARTH
_
Date
_
SCIENCE
Chapter 9
Minerals of the Earth's Crust
Review
Choose the best response. Write the letter of that choice in the space provided.
1. A natural, inorganic, crystalline solid with a characteristic chemical composition is called
a. an atom.
b. a gemstone.
c. a mineral.
d. a tetrahedron.
2. Minerals that contain silicon and oxygen are
a. sulfide minerals.
c. ores.
b. sulfate minerals.
d. silicate minerals.
3. The most common silicate minerals are the
a. feldspars.
b. halides.
c. carbonates.
d. sulfates.
4. Ninety-six percent of the earth's crust is made up of
a. sulfur and lead.
c. copper and aluminum.
b. silicate minerals.
d. nonsilicate minerals.
5. The basic structural units of all silicate minerals consist of
a. tetrahedral frameworks.
c. single chains.
b. silicon-oxygen tetrahedra.
d. double chains.
6. An example of a mineral with a basic structure consisting of single tetrahedra linked by
atoms of other elements is
a. mica.
b. olivine.
c. quartz.
d. feldspar.
7. When two single chains of tetrahedra bond to each other, the result is called a
a. single-chain silicate.
c. framework silicate.
b. sheet silicate.
d. double-chain silicate.
8. The appearance of the light reflected from the surface of a mineral is called
.c:
00
.~
.3
a. color.
b. streak .
c. luster.
d. fluorescence.
9. The words waxy,pearly, and dull describe a mineral's
a. luster.
b. hardness.
c. streak.
d. fluorescence.
Study Guide
Chapter 9
33
Name
_
MODERN
Class
EARTH
_
Date
_
SCIENCE
Chapter 9
Choose the best response. Write the letter of that choice in the space provided.
_ _ 10. The words uneven and splintery describe a mineral's
a. cleavage.
b. fracture.
c. hardness.
d. luster.
c. color.
d. luster.
_ _ 11. Mohs scale is used in measuring a mineral's
a. hardness.
b. cleavage.
_ _ 12. The ratio of the mass of a mineral to its volume is the mineral's
a. atomic weight.
b. density.
c. mass.
d. weight.
_ _ 13. The needles of the first magnetic compasses used in navigation were made of the
magnetic mineral
a. iron pyrite.
b. silver.
c. cinnabar.
d. lodestone.
_ _ 14. When calcite absorbs ultraviolet light and gives off red light, it is displaying the property of
a. radioactivity.
c. magnetism.
b. double refraction.
d. fluorescence.
_ _ 15. A mineral that is radioactive probably contains the element
a. uranium.
b. silicon.
c. fluorine.
d. calcium.
_ _ 16. Double refraction is a distinctive property of crystals of
a. mica.
b. feldspar.
c. calcite.
d. galena.
Critical Thinking
Read each question or statement and answer it in the space provided.
1. Natural gas is a substance that occurs naturally in the earth's crust. Is it a mineral? Explain how
you know.
34
Study Guide
Chapter 9
Name ___________________
Chapter 9 Minerals of the Earth’s Crust
Vocabulary: Number and define each term below in a complete sentence on a separate sheet of
paper. (Illustrate those with a *)
Crystal*
Cleavage*
density*
Double Refraction*
Fluorescence
Hardness
Inorganic*
Luster*
Mineral
Mineralogist
Mohs Hardness Scale
Nonsilicate mineral
Phosphorescence Refraction*
Rock-Forming Mineral Silicate Mineral
Streak
Silicon-oxygen Tetrahedra
8.1 What is a Mineral?
A. Definition of a mineral:
1. _____________- not made of living things or the remains of living things
2. _______________- formed in the Earth; not synthesized by humans
3. _____________- has a definite shape and volume
4. _______________________- is a single element or compound; can write a chemical
formula to describe it
5. ___________________- orderly internal arrangement of atoms
B. Types of Minerals
1. How many mineral have been identified, how many are common?
-Over _________ minerals have been identified, but fewer than ____ are common and
are called rock-forming minerals
2. Silicate Minerals
-Contain atoms of ______________and ___________, make up 96% of the Earth’s
crust
-Two examples of silicates: Feldspar and ____________ make up 50% of the crust
3. What are _______________ minerals classified into?
-Carbonates, Halides, Native Elements, Oxides, Sulfate, and Sulfides
-Ex: see page 158, table 9.1
C. Crystalline Structure
1. How do crystals form?
-Crystals form when liquid rock (magma or lava) cools, depending on the conditions
that existed determines the ____________________________
-The longer it has to form, the larger the crystal
a. Slow cooling forms large or ___________________ crystals
b. Fast cooling forms small or _________________ crystals
c. Very fast cooling forms no crystals or a _____________ texture
2. What is similar about all silicate minerals based on their crystal structure?
-Their crystalline structure is made up of the same building blocks consisting of four
______________ arranged in a pyramid with one ____________ atom in the center—
called a _________________________________________
3. What are the four types of silicon-oxygen tetrahedras?
-Single chain_________________
-Double chain- __________________
-Sheets- ____________
-Network silicates- ______________________
9.2 Identifying Minerals
A. Minerals have certain physical properties that can be used to identify them
1. Color- only good for a few minerals, because so many are different colors
Ex. __________________ is always green, _______________ is always blue, Quartz
comes in many colors, _______________ is always yellow
-Not a reliable test!- __________________ looks just like gold (called fools gold)
2. Luster- describe the way a mineral reflects light from its surface,
-luster is usually described as __________________ (iron, gold, silver, pyrite) or
____________________ (doesn’t reflect much light, not ‘shiny’)
-Quartz’s luster would be described as ______________
-Micas have a __________________ luster
-Diamonds have a ____________________ luster
-Minerals that lack any shine are considered ________________
3. Streak- the color of _______________________ off a mineral, the streak may differ
from the actual color of a mineral making it an excellent tool in identifying some
minerals
-ex. _______________ can be gray, green or black but always reddish-brown streak,
metallic minerals generally have a dark streak
4. Cleavage and Fracture- describes the way a mineral ___________________________
surfaces. If a mineral doesn't break along a smooth surface then it is known to
fracture,
-a rough surface is called _________________________
-a broken surface that looks like wood is called ________________________
-curved surfaces on a fractured mineral are called _____________________
-example halite always breaks in _________________ and mica along one surface.
-tetrahedral sheets such as mica break into _______________________
5. Hardness- the ability of a mineral to resist being scratched, a very useful tool.
- __________________________ developed a scale of hardness for minerals; the
lowest value was assigned to the softest mineral while the hardest mineral has a
value of 10 (_______________________)
-Mohs Hardness Scale
Mineral
Hardness
Talc
1
Gypsum
2
Calcite
3
Fluorite
4
Apatite
5
Feldspars
6
Quartz
7
Topaz
8
Corundum
9
Diamond
10
-The hardness of a mineral is largely determined by the strength of the
_______________________________________ that make up its internal structure
-Both a diamond and graphite are made up exclusively of
_______________________, diamond has a hardness of 10 due to the carbon atom
forming a strong crystal structure with four other carbon atoms, graphite is
arranged in layers that held together by weak forces
6. Crystal Shape- the way atoms or molecules come together determines the mineral's
crystal shape. There are six basic shapes: _________________________________
__________________________________________________ (see page 166)
7. Density- is the amount of matter in a given space, the density of a mineral is always
the same, galena will always be more dense than a piece of quartz the same size
-Formula: _________________________, measured in grams per cubic centimeter
B. Special Properties of Minerals
1. Magnetism- certain minerals, especially magnetite, have magnetic properties that
easily make them identifiable
2. Fluorescence - Calcite usually is white but under fluorescence light it appears red by
absorbing _________________________
3. Phosphorescence –when a mineral continues to glow after being exposed to
_____________________________
4. Double Refraction- when light rays are bent while going through transparent material
refraction occurs
-Calcite produces double refraction making a _______________________
5. _____________________-some minerals have unstable nuclei due causing them to
release particles and energy- ex. Uranium and Radium
5. Chemical Reactions- ______________ reacts with HCl (Hydrochloric Acid)
. Name _--..
----,.
_
MODERN
•
'Oass
EARTH
_
Oate
_
SCIENCE
Section 9.1
What Is a Mineral?
Read each statement below. If the statement Is true, write T In tbe space provided.
If the statement is false, write F In the space provided.
1. Silicate minerals make up more than 90 percent of the earth's crust.
2. The hardness of quartz is due primarily to bonds between oxygen and aluminum
atoms.
3. Plagioclase feldspar may contain sodium, calcium, or both.
4. Minerals are organic solids that are formed in the earth.
'.,
5. Sulfates and sulfides are types of nonsilicate minerals .
. Choose tbe one best response. Write the letter of tbat cbolce in tbe space provided.
6. Minerals made up of single chains of Si-O tetrahedra are called:
•
\.
-/
b. amphiboles.
a. pyroxenes.
c. crystals.
d. sheets.
7. Which of the following is an example of a mineral?
a. coal
c. steel
b. concrete
d. quartz
8. The minerals gold and copper are examples of:
b. organic compounds.
d. radioactive substances.
a. silicate minerals.
c. native elements.
9. How many oxygen atoms are in a silicon-oxygen tetrahedron?
I
a. 2
c. 4
b. 3
d. 5
_ _ 10. The structure presented in the diagram is an example
of a:
.
,
•
a.
b.
c.
d.
HRW material copyrighted under notice appearing earlier in this work.
tetragonal crystal.
hexagonal crystal.
triclinic crystal.
cubic crystal.
Chapter 9 33
Name
......
_
MODERN
Class
EARTH
_
Oate
_
SCIENCE
Section 9.2
.Identifying Minerals
Read eam statement below. If tbe statement is true, write T in the space provided.
If the statement is false, write F in tbe space provided.
.
1. Light rays are refracted or bent as they pass from one substance to a different substance.
2. The streak test is a test of mineral density.
3. Fluorescent minerals glow while being subjected to ultraviolet light.
4. Cleavage is important in identifying some minerals.
5. All minerals have the same basic crystal shape.
Choose tbe one best response. Write tbe letter of tbat cboice in tbe space provided.
6. The heft or relative weight of a mineral sample is directly related to the mineral's:
a. luster.
b. cleavage.
c. density.
d. hardness.
7. Needles of early compasses were often constructed of:
8.
lodestone.
b. calcite.
c. talc.
d. uranium.
8. Which of the following is an ore containing unstable nuclei?
8.
gypsum
Mineral
Hardness
feldspar
topaz
6
7
8
.corundum
9
quartz
b. feldspar
c. magnetite
d. pitchblende
9. According to the table, what is the approximate
hardness of a mineral that scratches quartz and can
be scratched by topaz?
6.5
b. 7.5
c. 8.5
d. 9.5
8.
_ _ 10. Diamond has which of the following types of luster?
a. metallic
34 Chapter 9
b. brilliant
c. glassy
d. pearly
HR W material copyrighted under notice appearing earlier in If
irk.
Geology
Name ______________________________
Lab: Specific Gravity
Date _______________________
Objective: To understand and apply the concept of Specific Gravity
**Specific Gravity represents the weight of a mineral in comparison to an equal volume of pure water. For
example, a mineral with a specific gravity of 4 is four times as heavy as an equal volume of pure water.
Specific Gravity is sometimes referred to as the density of a mineral.
Materials:
Procedure:
8 Minerals, graduated cylinder, scale, water
1. Determine the mass of the mineral
2. Use the water displacement method to determine the volume of the mineral.
(One milliliter = one cubic centimeter of volume)
3. Use the formula D= M/V to determine the specific gravity of the mineral
4. Repeat this for two samples of EACH mineral. Complete the chart.
Mineral Name
Mass (g)
Sample 1 Sample 2
Volume (cm3)
Specific Gravity (g/ cm3)
Sample 1
Sample 2
Sample 1 Sample 2
1. Quartz
2. Galena
3. Halite
4. Calcite
5. Pink Microline
Feldspar
6. Chalcopyrite
7. Magnetite
8. Hematite
Questions:
1. List the minerals, by name, from lowest to highest specific gravity.
2. Why is the specific gravity of galena so much greater than the specific gravity of quartz?
3. If the sample of calcite was cut into two equal pieces, what would the density of each half be when
compared to the density of the whole piece of calcite?
4. Compare your mineral densities with the listed density on page 666-667. List at least 3 factors
would affect the difference in mineral density.
Mystery Cube Density Lab
(Day 1)
Objective: To discover the identity of each cube based on its density.
Materials: Density cube set (9 cubes)
Hypothesis: If the mass and volume of a cube is found, then the density of the cube will determine the
material of the cube.
Procedures:
1. Find the mass of each cube using a balance and record results in the data table.
2. Find the volume of each cube (Length x Width x Height) and record results in the data table.
3. Calculate the density by dividing the mass by the volume and record results in the data table.
4. Identify the mystery cubes based on their densities from the chart below.
Known values for cube densities (g/cm3)
Acrylic = 1.1 – 1.2
Pine = 0.45
Aluminum = 2.7
Polypropylene = 0.90 – 0.92
Brass = 8.5
PVC = 1.4
Copper = 8.9
Steel = 7.9
Oak = 0.6 – 0.9
Results:
Cube #
Mass (g)
Volume (cm3)
Density (g/cm3)
1
2
3
4
5
6
7
8
9
Conclusion:
1. What determines whether a cube will float or sink in water?
2. Which cubes would sink in water?
3. Which cubes would float in water?
4. Describe how you determined the volume of the cubes.
5. Describe how you found the density for each cube.
Identity