Uses of Rocks &
Minerals
We use things made from rocks and minerals every day.
If something doesn't come from a plant or an animal, it has to be mined.
According to the Mineral
Information Institute, it is estimated that in a lifetime,
a person living
in North America will use up the following quantity of rocks and minerals:
- lead - 365 kg
- aluminum - 1633 kg
- zinc - 340 kg
- iron - 14 863 kg
- copper - 680 kg
- clays - 12 068 kg
- salt - 12 824 kg
(because of all of that road salt during our cold winters!)
- stone, sand, gravel
& cement - 562-773 kg
Very long ago, our ancestors used rocks for
tools. This was known as the Stone Age.
Obsidian and
flint were
used for knives and spears. River rocks
were used to break other things. Caves were used as places to live and
rocks and boulders
were used to sit on and to build fire pits. This period of human
development lasted a long time.
Depending on what part of the world people
lived in, this period was then followed by the
Copper Age
when people discovered how to smelt (melt using high heat)
copper ore. During
this time, cities were being built and
building stones were being used a lot. This
was then followed by the Bronze Age
about 6,000 years ago. During this time,
people learned how to mix minerals to produce metals like
copper,
bronze,
lead and
tin. This period was
then followed by the Iron Age
about 3,000 years ago.
Iron is very strong
and made very good and long lasting tools. These tools also meant that
stone could be
shaped more easily and many empires built buildings, structures and
roads that still can be seen today. Since that time period, people have
built many cities and used minerals extensively. In
Modern Times,
since about 1700 CE we have been using rocks and minerals at an ever
increasing rate as we build machines, cities and consume a great number
of "things" in a lifetime. Our uses of rocks and minerals can be divided
into 5 categories:
1. Building Stones
- Most of the rock used in construction
comes from quarries.
- Quarries are places where sand, gravel and
stone are excavated for building materials. Quarries are great
places to find fossil & mineral specimens as well since the blasting
of the rock exposes rocks that are beneath the surface.
- For more about quarries,
Click Here
Buildings
- Although wood, straw and mud is used for
houses in some parts of the word,
most cities today are built of stones and metal (minerals).
- Many rock & minerals are used to make
buildings. Concrete, steel, glass and wallboard are all common in
modern buildings.
- Granite is used to decorate the outsides
of buildings as well as tiles for floors and counters. It is a hard
stone that resists wear and weathering.
- Marble is used for interior walls and
floors where there is less traffic (such as bathrooms) because it is
soft.
- Many buildings built out of stone over
2000 years ago can still be seen in places where ancient
civilizations existed like Rome, Greece, Peru and Central America.
- Take a look at A Web Gallery of Stone
Buildings and their Building Stone
http://www.gly.uga.edu/railsback/BS-Main.html
Roads & Bridges
- A lot of crushed stone and concrete is
used in the building of roads, highways, tunnels, bridges, airports
and parking lots.
Aggregate
- Aggregate is what pieces of rocks that
have been blasted is called.
- The gravel you see in driveways & at the
side of the road are aggregate.
- Sometimes you won't see aggregate because
it has been mixed with cement to make concrete - the grey "stuff"
that sidewalks, buildings and curbs are made of.
- Aggregate can also be mixed with tar and
other ingredients to make asphalt - the black surface the school
yard is paved in.
- Quick Facts: Aggregates source: Ontario
Stone, Sand & Gravel Association (OSSGA)
http://www.apao.com/
- The average school requires 13,000
tonnes of aggregate (almost 650 truckloads)
- An average brick home uses 440 tonnes
of aggregate (22 truckloads)
- One kilometer of a six-lane road uses
51,800 tonnes of aggregate (2,590 truckloads)
- A typical large office building uses
16,000 tonnes of aggregate (800 truckloads)
2. Machines & Tools
- Many machines an tools are made of metals.
- Cars, planes and boats use many different
kinds of minerals.
- The process for making metals also
involves any other minerals in the smelting and refining process.
3. Artifacts
- Many things that we use every day such as
pens, filing cabinets, computers, coat hangers, cooking pots are
made of minerals.
- Pop cans and cars use a lot of metal. That
is why they should be recycled once we no longer need them.
4. Consumables & Processes
- We consume or use up rocks & minerals every day. The salt on our
food is a mineral. The gritty substance in our toothpaste is pumice.
The grit on our sandpaper is crushed garnets.
- The reason Canada consumes the most salt (per person) of any
country in the world is because we have many long roads and a lot of
snow in the winter. We use a lot of salt on our roads and sidewalks
to keep us safe.
5. Decorations
- Many sculptures are made of stone such as
marble, soapstone and jade.
- Many rocks and minerals are beautiful and
therefore decorative items are made from them.
- People have been making arts & crafts
using rocks & minerals for as long as people have been using tools.
- Some rock & mineral collectors display
their specimens like others display fine art.
- Many rocks and minerals are suitable for
use as decorations. For some background, take a look at
GemRocks
http://www.cst.cmich.edu/USERS/DIETR1RV/Default.htm
6. Jewelry
- When most people hear about diamonds, they
think of jewelry even though most diamonds are used in industry to
cut and polish softer rocks and minerals.
- People have been making jewelry for
thousands of years. Precious metals like gold and silver are the
most popular minerals used.
- Precious and semi-precious stones are used
because of their beauty.
- For some interesting articles on gemstones, visit GemSelect at
http://www.gemselect.com:80/other-info/other-info.php
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