Are diamonds rare? Compared to other precious gems, they actually aren’t. However, quality diamonds offer great value, whether in the form a natural diamond or a lab grown diamond. That is why mining companies invest billions of dollars setting up mines to obtain them. On average, a diamond mine moves about 250 tons of earth just to get a single carat of diamond.
Diamonds are essentially mineral deposits. If you are wondering how diamonds are formed and where diamonds are found, you should know that some diamonds are formed from Kimberlite volcanic eruptions, which create kimberlite rock. Kimberlite rock is an igneous rock that sometimes hides diamonds. Kimberlite is found in kimberlite pipes which are close to the earth’s surface.
There are a few different ways kimberlite is mined to find diamonds. The most common mining method options are alluvial mining, pipe mining, open-pit mining, underground mining method, and marine diamond mining. Note that there are other types of rocks that house diamonds as well, but general mining processes will be the same.
Alluvial mining is a simple mining process that mainly occurs on beaches and riverbeds. Many years of wind, rain, water currents, and erosion carries diamond deposits downstream from their direct deposits of kimberlite to riverbeds and beaches. These alluvial deposits are often mined from old rivers.
Mining alluvial deposits can sometimes be as simple as panning through the gravel in a stream. However, it can also be as complex as constructing large projects which control and divert the river water to expose diamond-bearing gravel. Today, industrial alluvial mining is a complex project that involves building a giant wall to control and collect water in one specific area. That area is where miners look for diamond deposits.
Diamond deposits are often found in the gravel layer, which allows miners to collect them easily. They also mine them from layers of other material such as clay, mud, and underwater plant life. After collecting the gravel from the under layers of material, it’s hauled to the earth’s surface where it’s prepared for processing. Once this stage is reached, diamond deposits are then processed to form different finished products.
Pipe mining actually includes two types of processes, open-pit mining, and underground mining. So keep reading for the specifics on both.
Open Pit Mining
Open-pit mining starts with an excavation of the pit in a kimberlite pipe. This is the process of removing the layers of rock and sand that are found above the kimberlite. Miners move the layers of sand and rock closer to the surface to process and extract diamond deposits from it.
It might be challenging, but miners employ techniques that make it easier for them to collect these deposits. The weathered materials are then removed with ore trucks and hydraulic shovels.
Ore that’s found in the constructed pit is broken by blasting. Hard rock is usually drilled and then blasted using explosives. After being broken, the ore is then loaded and transported to the primary ore crusher for further processing. At this stage, the diamond extraction process begins.
Underground mining is when miners create a tunnel through the earth’s crust to access a kimberlite pipe. These tunnels are built parallel to each other with one slightly above the other. Then funnels are built in between to connect the two tunnels.
Mining starts when the miners in the top tunnel blast the ore. It then falls through the funnels and collects on the bottom tunnel. When this process has finished, loaders pick up the broken ore and transport it to the surface for further processing.
Marine mining actually involves extracting diamonds from the ocean floor, a hundred meters underwater. The earliest form of marine mining involved divers diving into the sea to collect the diamond-bearing gravel deep in the ocean.
Today technology has made it more accessible. Ships that feature specialized equipment suck gravel from the ocean bed up through the flexible pipes or hoses. Alternatively, they can use a large-scale drill that is mounted on the ship to excavate the diamonds.
Additionally, marine mining is divided into horizontal and vertical marine mining.
Horizontal marine mining involves mining a diamond using a crawler that sucks the gravel from the seabed to the surface using flexible pipes. Vertical mining involves mining diamonds using large ships mounted with a drill to remove the diamond gravel from the seabed.
Diamonds are precious minerals that undergo several different stages to become the valuable gem we all know and love. Many techniques are employed to mine them successfully. Their journey from start to finish is undeniably long.
So, is it ethical to buy diamonds? The answer is complicated. Mining’s environmental and human impact are well known and substantiated. Some stones sourced from mining are even conflict diamonds or blood diamonds. If you would like to learn more about blood diamonds check out our article about blood diamonds and where they come from.
If we still can’t convince you to stay away from mined diamonds, be sure to conduct avid research before making any purchases. Better yet, choose a lab grown diamond or a diamond alternative instead.