DR MICHELINA ANDREUCCI
It has often been said that the discovery of minerals brought civilization in its wake. From the flint axe of Stone Age ancestors to the titanium of space age and today’s technology, the discovery and use of minerals has been the measure of man’s progress.
With the exception of atmospheric gases, everything that man uses comes either directly or indirectly from the earth’s crust.
This applies not only to mineral products such as metals and ores, coal, petroleum, ceramic clays, building and construction materials such as cement from lime deposits, etc., but also to plant and animal products.
In addition, the essential salts necessary for the development and support of all forms of life are ultimately derived from the crust of the Earth through the medium of either the soil and/or water.
The natural resources of any country include all the latent wealth inherent in the soil, climate,
topography, mineral deposits, etc., together with the physical and mental qualities of its people.
Just under two centuries ago little was known of the geology and mineral deposits in Zimbabwe with the exclusion of the fabled vast gold reserves that first attracted Cecil John Rhodes and the early pioneering columns. Since then, through implacable, trackless bush, almost every part of Africa, Zimbabwe including, has been geologically mapped.
However, it became apparent that mineral deposits were not dispersed evenly throughout the Continent.
Instead, they tend to be associated with particular rocks, and results from particular natural processes that confine them to particular areas of which Zimbabwe has in abundance.
A mineral is defined as any homogeneous, naturally occurring constituent of the earth’s crust. They include substances such as common salt or diamonds, crystalline, liquids such as water or petroleum and gases like helium or methane gas. The aggregate of one or more of these minerals form naturally into rock.
The Precambrian rocks that form the foundation of Zimbabwe and the African Continent, are the oldest group of rocks on Earth. They include sedimentary rocks, formed from materials transported by water and wind; igneous rocks solidified from molten minerals, and metamorphic rocks produced by the reconstitution of sedimentary and igneous rocks through the action of heat, pressure and natural fluids, deep in the bowls of the Earth.
Studies indicate the period of formation spans a minimum of four-fifths of the history of the Earth’s crust; the average age of the youngest of the rocks is approximately 600 million years old and the oldest over 3 000-years old.
Many important mineral deposits are related to the hot mobile rock-forming material within the earth known as magma.
As magma cools, various combinations of elements crystallise and in turn form minerals of different compositions; together these minerals form igneous rocks. There are however, only infinitesimal amounts of most of the more familiar and desirable substances present in the earths crust and cannot not always be extracted economically.
It is the task of geology to determine the conditions under which localised concentrations of the
various elements are formed. The localisation of mineral concentration and the processes involved will inform a geologist to estimate the probable occurrence of ore bodies in a given area, its profitability and best method of extraction.
Based on territorial assets, most regions are differently endowed in respect of natural and mineral resources; these provide a benchmark for economic development. A nation’s natural resources, in the form of minerals, constitute a comparatively fixed un-renewable quantity, subject to modification within narrow perimeters.
To make full use of resources that lie within the earth, it is necessary to know the nature and extend of available resources and the best means of obtaining and employing them. This requires large expenditure in terms of time, money and effort and particularly scientific and technical man-power.
Therefore, geological fieldwork in Zimbabwe requires in-depth knowledge of the problems and methods of solving them.
One of the most important issues that confront Zimbabwe today is concerned with the economic advancement of the State and its people. Along with agriculture, the mining sector is a key pillar of Zimbabwe’s economy. Mining in Zimbabwe is a major contributor to the National economic development and accounts for almost 50% of Zimbabwe’s total foreign currency revenues.
With 48% of the world’s strategic mineral resources, Zimbabwe has significant reserves of platinum, diamonds gold, coal, gold, platinum, copper, nickel, tin, including numerous metallic and non- metallic ores, making the mining industry a vitally important economic mainstay for Zimbabwe.
Yet, in our ever-increasing appetite for mineral wealth the ongoing mining projects have been criticized for their unregulated environmental impact and minimal social stewardship.
Minerals are essential raw materials in our daily lives, and vital for economic, social and technological development.
Minerals also play an important role in agriculture. For example, nitrogen, potassium, phosphates, lime and other essential elements derived from minerals can be added to improve soil quality to obtain maximum agricultural output and improve food sustainability.
Applications of mineral fertilizers not only produce higher yields, but also denser crop growth; this dense growth protects arable lands from erosion and saves soils for the future.
The water we drink uses minerals to make it clean.
In construction minerals are used in building houses, schools, libraries, hospitals, offices and shops.
Buildings use a wide range of minerals:
iron (as steel) in the framework of large building,
clay in bricks and roofing tiles,
slate for roofing tiles,
limestone, clay, shale and gypsum in cement,
gypsum in plaster,
silica sand in window glass,
sand and gravel and crushed rock as aggregates for fill and in concrete,
copper for plumbing and wiring,
clays for bathroom fixtures and fittings and tiles,
paints may include pigments, extenders and fillers from mineral sources.
Whilst Government has put into place programmes to improve the planning and management of land resources and developed environmental operating guidelines for the various sectors, land degradation is one of the major environmental problems in Zimbabwe especially in communal areas.
A large amount of biodiversity has been lost to mining activities, together with traditional socio-cultural role of the environment, linked to the growing poverty in rural areas.
According to Dr. Tony Monda “Our economy, wealth, land, waters and natural resources are our children’s birthright. We are duty bound by the Almighty to manage and preserve this birthright as equitably and prudently as we can for them”. This begs the question: Are Zimbabwe’s vast natural resources a key of progress or deprivation?
Michelina Andreucci is a Zimbabwean-Italian researcher, and a published author in her field. For Comments E-mail: linamanucci@gmail.com
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