Name: ___________________________
Block: ________
KW Mineral Packet
A mineral is a naturally occurring inorganic solid with a distinct chemical composition and crystalline
structure. The five characteristics a substance must have to be classified as a mineral are:
1. It occurs naturally (not man made)
2. It is solid
3. It has a definite chemical composition
4. Its atoms are arranged in an orderly pattern (like a crystal)
5. It is inorganic (was never alive)
The two most abundant mineral-making elements are oxygen and silicon.
Minerals form from molten rock. As magma cools, the atoms, molecules and ions move closer together and
form chemical bonds that create compounds. The size of the crystals is determined by the rate at which magma
cools. If the magma cools quickly, the crystals do not have much time to form, so they are very small. If the
magma cools slowly, then the crystals have enough time to grow and become large. A crystal is a regular
geometric solid with smooth surfaces. There are six basic shapes of crystals including cubic and hexagonal.
Minerals can also form from evaporation. Evaporate minerals are those that form by coming out of solution
when seawater and the waters of large lakes evaporate. Halite forms when water evaporates from a solution of
salt and water.
Figure 3.23: The limestone towers are made mostly of calcite deposited in the salty and alkaline water of Mono
Lake, in California. These rocks formed under water when calcium-rich spring water at the bottom of the lake
bubbled up into the alkaline lake, forming these calcite "tufa" towers. If the lake level drops, the tufa towers
appear in interesting formations.
Types of minerals:
Silicate Minerals - minerals that contain a combination of silicon and oxygen. They make up 90% of
the Earth's crust. Families of silicates include:
 Quartz
 Feldspars
 Pyroxenes
 Mica
 Amphibole
 Kaolinite and the Olivine group
Nonsilicate Minerals - minerals that do not contain a combination of the elements silicon and oxygen.
There are six classes of these elements.
Six classes of nonsilicate minerals:
1. Native elements - minerals that are composed of only one element.
2. Carbonates - minerals that contain combinations of carbon and oxygen.
3. Halides - compounds that are formed when atoms of the elements fluorine, chlorine, iodine, or bromine
combine with sodium, potassium, or calcium.
4. Oxides - compounds that are formed when an element, such as aluminum or iron, combines chemically
with oxygen.
5. Sulfates - contains sulfur and oxygen.
6. Sulfides - minerals that contain one or more elements, such as lead, iron, or nickel, combine with sulfur.
https://www.youtube.com/watch?v=TwgGPtqZnQc
Non-silicates 5:01
Identifying Minerals – Different Properties
COLOR is the least useful property in mineral identification because many minerals have similar colors.
Impurities can turn colorless minerals into colored minerals.
 Metallic minerals have distinct colors
 Nonmetallic minerals display a variety of colors
LUSTER is the way the mineral shines in light. Two main classifications of luster are metallic (looks like
metal) and nonmetallic. Nonmetallic luster is further divided into (but not limited to):
 Vitreous – Looks like glass (quartz)
 Adamantine – Brilliant like a diamond
 Resinous – Looks like resin or tree sap
 Pearly – Looks like a pearl (mica)
 Silky – Having a fibrous silk-like luster
 Earthy or dull – Looks like dirt
https://www.youtube.com/watch?v=MuJN-H52mGM
https://www.youtube.com/watch?v=rtc7XJdFiE4
Chumley – Gold vs. Fool’s Gold
Quartz – Vitreous Luster
Barite – Pearly luster
Anglesite – Adamantine Luster
Sphalerite - Resinous Luster
Actinolite – Silky Luster
Azurite – Earthy Luster
CLEAVAGE is the tendency to break along definite planes and is determined by crystal structure.
 Some minerals cleave in sheets and some cleave leaving flat sides.
 Some minerals have cleavage in more than one direction.
 Some minerals have no cleavage at all.
https://www.youtube.com/watch?v=cxtIvxUd4DY
FRACTURE is the way a mineral breaks when it does not have cleavage. Kinds of fracture:
 Conchoidal- bowl shaped structures like the inside of a clam shell; like obsidian
 Fibrous or splintery- fractured surface shows fibers or splinters; like asbestos
 Uneven- this surface is rough and irregular; like basalt
Obsidian – Conchoidal Fracture
Chrysotile – splintery fracture
Talc – uneven fracture
https://www.youtube.com/watch?v=eeT068wxsVQ
STREAK is the color of a mineral’s powder. It is tested by rubbing the mineral on an unglazed white tile
called a streak plate.
 The streak is often a different color from the mineral.
 Streak is much more consistent than color for the purpose of identification.
 The streak of a metallic mineral is at least as dark as the specimen.
 The streaks of nonmetallic minerals are usually colorless or white.
https://www.youtube.com/watch?v=wENW59poN8Q
HARDNESS measures the ability of a mineral to resist scratching by another mineral or object of known
hardness. Hardness depends on chemical structure.
 A diamond is carbon atoms arranged in a
tetrahedral pattern.
 Graphite is carbon atoms arranged in sheets.
MOH’S HARDNESS SCALE

Moh’s Hardness Scale is a scale used to measure the
relative hardness of a mineral by its resistance to
scratching, made up of ten minerals arranged in
decreasing hardness; 1 is the softest and 10 is the
hardest.

Objects with higher value on the Mohs' scale are capable of scratching objects with lower values.
https://www.youtube.com/watch?v=R-bw7_u3gSQ
SPECIFIC GRAVITY is the ratio of a mineral’s mass to the mass of an equal volume of water. Density is
mass divided by volume. D = M/V.
https://www.youtube.com/watch?v=yGnNE-MWDV4
SPECIAL PROPERTIES
 Calcite can be tested with hydrochloric acid (HCL) because it fizzes when it comes in contact
 Fluorescence is a property of certain minerals: when you shine an ultraviolet "black light" on them in a
darkened place, they respond by glowing in strangely bright colors.
 Double refraction splits light rays that pass through it such as Iceland Spar calcite.
 Magnetite is attracted by a magnet.
 Taste
 Smell
https://www.youtube.com/watch?v=AK_Z63UvQjE
https://www.youtube.com/watch?v=iS0pWYHSh84
https://www.youtube.com/watch?v=xrR14fBXpsM
MINERAL
Calcite
Copper
Diamond
Feldspar
Galena
Graphite
Gypsum
Halite
Hematite
Muscovite Mica
Quartz
Silver
Sulfur
Talc
HCL
Black light
Magnetite
USES
Medicine, toothpaste, building materials
Tubing, Wires
Cutting Tools
Ceramic, Porcelain, Found in granite
Lead
Pencils, Lubricants in Machines
Wall board
Salt
Iron
Electrical insulators, Cosmetics
Glass, Radios, Watches
Jewelry, Photography
Fungicides, Medicine, Vulcanizes Rubber
Fertilizer, Coal & fuel, Baby powder, Gymnastics to grasp bars
https://www.youtube.com/watch?v=SqSOskpMsxM