RocksforKids

Rocks in Building

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. This period of human development lasted a long time.

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.

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 Photos of Quarries & Aggregates

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)