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Our Products |
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McCallum Bros. Ltd. supplies high quality sand suitable for the building industry.
Sand is an important commodity for the building industry. High-quality sands (defined by their mineral content, grain size, and the absence of components such as high shell content, organic material and clays - which all reduce the strength of concrete) are primarily used in the production of ready-mixed concrete. |
Other sand is used in landscaping, sportsfield drainage, beach replenishment and industrial use. |
Sand Use |
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Summary of Sand Use in the Auckland Region
Industry Sector |
% Use |
| Ready-Mixed Concrete |
55 |
| Construction Industry |
25 |
| Manufacturing |
10 |
| Industrial |
10 |
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Sand makes up nearly a third of concrete. With 1.27 million m³ of concrete produced in the Auckland region per year (calculated at 10 March 2005 by Department of Statistics), 420,000 m³ of sand is required in the Auckland region for this use alone. |
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Sources of Sand |
Offshore coastal sand extraction is a significant source of sand throughout the world including Britain, France, Germany, Holland, Denmark, Sweden, Belgium, United States, Taiwan, South Korea and Japan. The main source of sand for Auckland’s building industry (as with similar regions around the world) is from marine coastal deposits. |
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Extraction Methods |
In the Auckland Region, marine coastal sand extraction is typically carried out using suction dredges. Sand is screened using mesh sizes of the order of 3 mm. The material caught on the screen (including shellfish, snails and other marine life) is returned to the seabed.
The location of sand extraction is at a depth which is a very active zone due to the surf wash. Conditions are harsh and most animals cannot cope with the constant battering they are subjected to so there are few animals present.
Those that are present (sand dollars, hermit crabs and various worms) are common throughout New Zealand, some are able to survive the dredging process while others recolonise the dredged area quickly. |
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