Uses of Rocks &
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
History - How we used Rocks & minerals way
- Very long ago, our ancestors used rocks for
tools. This was known as the Stone Age.
- This period of human development lasted a long time
- about 3 1/2 million years.
- This is also known as
- This era ended about 4,000 to 6, 500 years
ago when people learned how to make metal.
- Obsidian and
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.
- Depending on what part of the world people
lived in, this period was then followed by the
when people discovered how to smelt (melt using high heat)
- In Britain, it was about 4,500 years ago
and lasted for several centuries
- This was not a long period because people
quickly learned how to make other metals.
this time, cities were being built and building stones were being used a lot.
was then followed by the Bronze Age
about 6,000 years ago.
- Bronze is an alloy of copper.
- During this time,
people learned how to mix minerals to produce metals like
- Smelting ore
is when you melt crushed rocks with minerals in them at very high
temperatures. By adding other chemicals and minerals, the metals
separate out and the metal can be poured off. Smelting is like
melting with a purpose.
- The melted rock that is not metal is
- This period was
then followed by the Iron Age
which started about 3,000 years ago.
- During the Bronze Age they learned how to
extract / make metal from rocks. During the Iron Age they learned
how to make tools & implements (things they used) out of metal.
- 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 (or 400 years ago) 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:
Web Sites that Discuss
Minerals & their Uses
Minerals – Colors for walls and faces© Bert Ellison 1999
The term "Redskin" probably was first applied by Europeans who
encountered the natives of Newfoundland. These early Canadians – Beothuks or
Mic-Macs? Painted themselves with some red pigment, probably iron oxide
There was certainly a lot of it available on Bell Island near present St. John’s
and it later became a big source of iron ore. In western Canada and US scattered
deposits of this red and also yellow-brown earth were valued sources of color
("war paint") and widely traded. In the caves of Europe, Africa and
Australia are wall paintings of not only the authors’ hands but the animals
they hunted. White clays and chalk added variety to these age-old records.
Minerals of various kinds and forms thus provide we moderns with a fine
account of ancient times. Here are some examples of colors and sources:
- Dull reds from hematite and ochres – natural earths.
- Yellows and oranges from iron-rich ochres and later joined by modern
compounds of chromium, zinc and cadmium.
- Greens from malachite Cu2(OH2)CO2
– a copper carbonate.
- Blues from azurite Cu3(OH)2(CO3)2
- also copper carbonate.
- Crimson red from cinnabar (HgS), source of mercury, was a favorite lip
color for Elizabethan women with lethal results – and for the men too!
- Black of stibnite (Sb2S3)
or kohl is still used to darken around eyes and formerly in the eyes to
stain the whites blue and to add glitter – and eventually blindness.
- More black? How about iron sulfide, graphite and galena? The latter is
more abundant than antimony and was also used to darken hair and eyes. Even
today Grecian 2000 formula contains lead acetate.
- More yellows? Would you believe from orpiment (As2S3)
or realgar (AsS) both arsenic compounds, mixed with cadmium (Cd) or gold to
color hair yellow in 19 Century Britain. Surely those
"blondes" didn’t have more fun!
- White was relatively easy to come by from chalk (CaCO3)
titanium dioxide (TiO2),
widely used today in paints. Then there is zinc oxide (ZnO), barite (BaSO4)
and white lead (cerussite?) (PbCO3).
- Browns? There is umber (iron and manganese clays) both raw and
- For blues and greens, the Greeks powdered glass containing copper.
- Other blues? If money, time and labor matter not, try grinding
semi-precious sodalite or lapis lazuli.
- We’re hardly surprised that the thrifty, early railroads of Canada used
"box-car red" – hematite, cheap and seemingly ever-lasting.
- Finally, even whodunits combined lace with arsenic!