Visiting a quarry while studying rocks & minerals can be
one of the highlights of your learning.
We are fortunate that in Canada that we
have many good sources of building stones and aggregate – namely sand, gravel
and crushed rocks. Here in Ontario, there are many working quarries that welcome
visits by school groups. The Ontario Stone, Sand & Gravel Association
keeps an up to date list of companies that offer
school tours at
http://www.ossga.com/tours.htm . The quarries visited by my grade 4 class
in the last few years include:
We watched how quarrying was done and sand was produced
at the Burlington Quarry operated by the Nelson Aggregate Co.
We visited a glacial deposit gravel pit in Limehouse
courtesy of J.C. Duff Limited.
At the Milton Quarry operated by
Dufferin Aggregates we saw how quarries that are no longer being used
are rehabilitated into wetlands.
Quarries are very important in our lives.
In North America, we use up about 500,000 kg of stone, sand, gravel and cement
per person in a lifetime. That is a HUGE amount. Of course you
don't use it all up, nor do you use it at home. The reason the number is so high
is because we all use roads, airports, schools, buildings, and anything else
that needs crushed stone.
Many quarries for crushed stone use
limestone which is a sedimentary rock. Not only can you find fossils in
limestone, but mineral specimens are also found.
Since the rock is blasted and crushed
into smaller pieces, quarries are a great place for Rockhounds because a lot of
the hard work of breaking up the rock is already done. The Mining Act has rules
about quarries because of safety issues. Quarries are all on private property
and may not be entered without permission.
Another word for crushed stone is
"Every year, the people of Ontario
consume approximately 173 million tonnes of aggregate. That is about 1 truck load for every man,
woman and child in the province! We all share in the responsibility for the
demand for aggregate materials. Through responsible land stewardship, innovative
operations, creative rehabilitation and responsible marketing, the
aggregate industry is minimizing the impacts and maximizing the benefits
that aggregates provide to the province of Ontario."
http://www.jcduff.com/ J.C. Duff Sand & Gravel is proud to
have been one of the FOUNDING members of the APAO (1956).
For an interesting look at the Quarry Industry's
perspective, check out The Hole
Story, a web site maintained by the Ontario
Stone, Sand & Gravel Association