The planet earth where we live and breathe is composed of multiple layers. Its inner layer is made up of liquid while the outer layer is solid in nature. The part where we live is called the earth’s crust.But this crust was not like this always. More than four billion years ago, this crust was molten. And when it began to cool continental nuclei and it’s the cores were formed.
This nucleus was based on the areas of South-central Canada, Brazil, some parts of Russia, Australia, and South Africa. That is how they became home of the world’s oldest, or Archaean, rock.
The specialty of this rock is that it contains gold, iron, and manganese. But to produce minerals from rocks, only possession is not enough. Meaning, for rocks to yield their minerals readily, they must be exposed to the natural environment. And sadly, a lot of areas could not provide the required atmosphere.
Unfortunately, due to the lack of a compatible environment, many countries were not able to use the rocks. Like Brazil’s Archaean rock came to be covered by the Amazonian rain forests. Canada’s by glacial debris. Russia’s with steppes. And, Australia’s got covered with the thick soils of the outback.
In this matter, South Africa was fortunate. South Africa’s rock remained relatively unchanged by geological events. Even its weather system helped the process. The ancient rocks got eroded in such a way that some of the minerals, particularly gold, have been re-concentrated in sediments near the surface.
The above scenario explains South Africa’s wealth of easily accessible gold, iron, and manganese. But what of its other treasures? Well, these resources are another consequence of simple luck.
The tip of Africa happens to be a ‘geological crossroads’ where continents have built up and broken apart over time. When continental nuclei rupture, the molten rock rises through the rifts, resulting in igneous rocks that fill the cracks.
There are many such extrusions of igneous rock in the world, but the effects of rifting have been especially dramatic in South Africa. About 1.8 billion years ago South Africa’s Bushveld Complex, the biggest single igneous rock body on the face of the Earth (roughly the size of Ireland), was formed, leaving behind huge deposits of chromium and platinum.
Not only this, but the Rifting also led to the formation of diamond fields about 100 million years ago. The molten rock that rose from rift intersections in South Africa contained pipes of kimberlite, which carry fully formed diamonds from great depths. Hence, all this explains their South Africa being the rich source of diamonds.
However, South Africa isn’t the only land blessed in this regard. Arkansas, Wyoming, and Western Australia also faced rifting. And as a result of that, they also have diamonds very similar to the ones in South Africa. But their kimberlite pipes aren’t as large or well-formed, and therefore can’t carry as many big, high-quality diamonds up to the surface.
In short, South Africa was just plain lucky. Its kimberlite pipes are deep and protrude prominently through the brittle, ancient crust. Geological fate has indeed been very kind to South Africa. The rock there is readily available to be mined. And that is why this country is considered to be one of the highly mineral-rich lands on the planet.