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What Kind of Rocks Are Diamonds Found In?

What Kind of Rocks Are Diamonds Found In?

If you have had the opportunity to read the articles that we have published on our blog, we are sure that you know that we do not reduce writing to just a simple answer to a question.

We try to prepare a lot of helpful information, research, and verify for you to get a clear picture of the topic that interests you.

So, the question and topic we will deal with today are: What kind of rocks are diamonds found in? The original answer, as well as the simplest one we prepared, is that:

Diamond can only form under extreme pressures. Kimberlite, an ultrabasic volcanic rock created deep inside the Earth’s crust, contains it.

But let’s see what else is essential for you to know so that you can understand the answer we have given you and get the best possible picture of the formation of diamonds.

What Exactly Are Rocks?

First things first- let’s get to know what rocks are!

Rocks are classified into three types based on how they were produced. Sedimentary, igneous, and metamorphic rocks are the three types of rocks.

Sedimentary rocks form in water when layers of sediment accumulate over time. Sandstone, flint, and chalk are examples of sedimentary rocks.

When lava cools and solidifies, it forms igneous rocks. Basalt, granite, obsidian, and pumice are examples of igneous rocks.

Metamorphic rocks are so named because they transform due to pressure and heat. Marble, granulite, quartzite, and slate are examples of metamorphic rocks.

Rocks can provide valuable information about Earth’s history.

Rocks are records that can teach scientists a lot about what the Earth looked like and what the atmosphere was like long ago.

Scientists can better understand why and how the planet is the way it is today if they know its history. Scientists can also predict what will happen to Earth in the future.

Rocks develop under certain conditions, so when scientists discover specific gems in specific locations, they may make educated guesses about the environmental conditions that had to be present for the stones to be found.

Related Read:

What Exactly Are Diamonds?

Let’s start with the main differences – diamonds vs. graphite?

Diamonds, the hardest materials on the planet, are found beneath the Earth’s surface. Four particular events must occur for a diamond to develop.

Carbon must exist, and then pressure and heat must be applied to the carbon over time.

The temperature must be at least 752°F, and the pressure must be at least 434,113 pounds per square inch.

Diamond is a polymorph of the element carbon, as is graphite. While they have the same chemistry, C (elemental carbon), their structures and characteristics are vastly different.

Diamond is an excellent electrical insulator, whereas graphite is a strong electrical conductor.

Also, diamond is the ultimate abrasive (its primary application), whereas graphite is an excellent lubricant.

Diamond is translucent, but graphite is opaque. This is because diamond forms in the isometric system, while graphite forms in the hexagonal system.

At surface temperatures and pressures, however, graphite is the most stable form of carbon.

In reality, all diamonds on or near the Earth’s surface are now undergoing a transition into graphite, albeit at an incredibly sluggish rate.

The optimal depth for diamond formation is around 100 miles below the Earth’s mantle.

Volcanic explosions at some time raised diamonds to these great depths, making them simpler to discover.

If you found a diamond in the mud, it would not be dazzling and shining. Diamonds only seem dazzling and scintillating after they have been cut and polished.

Another great diamond facts:

  1. Diamond is transparent to more wavelengths than any other material, ranging from ultraviolet to far infrared.
  2. Diamond transmits heat better than any other material, five times better than silver.
  3. The melting point of the diamond is the greatest of any solid (3820 degrees Kelvin).
  4. The atoms of diamonds are packed closer together than in any other solid.

We’ve covered the basics, but don’t blame us; this topic must include more technical descriptions and details!

Related Read: How Far Below the Earth’s Surface Are Most Diamonds Crystallized?

What Are Minerals?

Minerals are defined differently by geologists. A substance has to fit five scientific rules to be called a mineral. Minerals occur naturally, and they are inorganic.

To be clear with what is “naturally occurring”: Naturally occurring objects are things that people have not made.

Also, inorganic objects are things that organisms have not made. Wood, for example, is natural, yet it is derived from trees. As a result, wood is not a mineral. Minerals are solid materials with a specific chemical makeup.

A fixed chemical composition indicates that the content of all occurrences of a mineral will only vary within a specific range. At average temperatures and pressures, solids are neither a gas nor a liquid.

Minerals, finally, have an organized internal structure. This indicates that the atoms in a mineral are organized in a predictable and recurring pattern.

The objects you see and touch around you are made of a mineral mixture.

People use a wide range of minerals in their daily lives. For example, scientists estimate that the United States consumes around three trillion tons of minerals annually.

Each American resident equates to around 10 tons of minerals yearly.

Methods of Diamond Formation

Many people believe that diamonds form as a result of coal metamorphism. Also, many science classes still teach the “how diamonds form” myth.

Coal has never been used in the production of diamonds. Most dated diamonds are far older than Earth’s first land plants – the primary material of coal.

That alone should be enough to contradict the claim that coal-generated the most valuable stones on the planet, diamonds.

Another issue is that coal seams are sedimentary rocks frequently occurring as horizontal or nearly horizontal rock groupings.

On the other hand, diamond source rocks are vertical pipelines filled with igneous elements. Almost all natural diamonds found at or near the Earth’s surface are thought to be the product of four processes.

One of these procedures is responsible for nearly all diamonds ever mined. The other three are minor commercial diamond sources.

What Kind of Rocks Are Diamonds Found In?

Finally, we are here to address our main question: What kind of rock are diamonds found in?

Only through tremendous pressures can a diamond form. It is found in kimberlite, an ultrabasic volcanic rock formed deep inside the Earth’s crust.

Pipes of the minerals kimberlite and lamproite are frequently found in the Earth’s upper mantle, and their pipe “trails” include diamond crystals.

These minerals are weather resistant and denser than quartz sand. Kimberlite and lamproite float to and assemble in streambeds as a result.

Because these pipes often contain diamonds, geologists refer to them as “indicators” when they are discovered in gravel-dense streambeds.

Kimberlite, commonly known as blue ground, is a dark-colored, massive, often altered, and brecciated (fragmented) intrusive igneous rock containing diamonds in its rock matrix.

The texture is porphyritic, with massive, frequently spherical crystals (phenocrysts) surrounded by a fine-grained matrix (groundmass).

It is a mica peridotite with olivine as the most prevalent mineral ingredient.

Other abundant minerals include:

  1. phlogopite mica,
  2. chromium
  3. Pyrope-rich garnet phenocrysts,
  4. chrome-bearing diopside

Kimberlite, like lamproite, is vital for bringing diamonds to the crust via magmatic intrusions. As a result, they consolidate into pipeline structures.

Kimberlite may be found at the raised centers of continental platforms.

It generates pipes (more or less oval-shaped funnels that constrict with increasing depth) and, occasionally, dikes in South Africa’s Kimberley province.

Other examples are the dikes in Ithaca, New York, the Kimberley and Lake Argyle regions of Australia, and the lavas in Tanzania’s Iswisi Hills.

Diamond Mining

Mining is the world’s fifth-largest industry. It is critical to global economic growth, and trading in mineral commodities accounts for a large percentage of worldwide markets.

About 147 million carats were mined in 2018, with a global market valued at $76 billion. Eleven percent came from the Democratic Republic of the Congo, 29% from Russia, and 16% from Canada.

The Republic of Sakha (Yakutia) produces 99% of Russia’s diamonds, worth US$1.5 billion annually, and accounts for 20 to 25% of global output (Yakovleva et al., 2000).

Botswana, Canada, Angola, and South Africa are the top five nations regarding gem-quality diamond output, with Russia housing half of the vital diamond mines.

The intended distinction of “world’s largest diamond mine” is subjective.

Mineral resource exploitation irreversibly impacts the environment in addition to deforestation, soil disturbance, air emissions, surface water pollution, groundwater contamination, dust, noise, worker health and safety, and other challenges.

Mining allows any country in the world to develop and prosper.

Through construction infrastructures such as roads, trains, and employee townships, the consequences of diamond mining can spread well beyond the local region of operations.

They can also influence the local community by affecting public health and indigenous cultures’ property rights.

Again, Russia, Botswana, Australia, the Democratic Republic of the Congo, and Canada are the top five diamond-producing countries.

Let’s get started with the mining process!

Related Read: What Are Negative Effects Of Diamond Mining?

The Process of Diamond Mining

Unlike other mining procedures, diamond mining does not use chemicals (such as the cyanidation of gold). As a result, even if there is less associated environmental damage, the four-diamond mining techniques still represent considerable short- and long-term risks:

1. Open Pit Mining

After layers of rock and soil are removed, the ore beneath is blasted to allow for removal. The unprocessed material is loaded onto trucks and sent to a crusher plant.

2. Underground Mines

Two levels of tunnels are dug and linked by funnels deep into the earth’s crust, a technique known as “hard rock mining.” When the ore is blasted in the first tunnel, it falls and lands in the second. It is then seized by the hand and dragged to the top.

3. Marine Diamond Mining

Among the most recent mining advances, this method of diamond mining connects crawlers to ships to gather seabed gravel, which is then processed. Naturally, this only happens in nations with access to water.

4. Artisanal alluvial mining

Industrial mining is difficult since alluvial diamonds are commonly encountered in many beds. As a result, small-scale diamond extraction is typically done by hand and frequently without regulation.

These were the four different kinds of diamond mining!

Final Thoughts

If you asked yourself the following question out of curiosity: What Kind of Rocks Are Diamonds Found In? We have tried not only to answer it but also to expand the story about diamonds so that you can acquire new and necessary knowledge related to diamonds.

We will agree that the answer we gave to an expert is that Diamond can only form under extreme pressures. This is because kimberlite, an ultrabasic volcanic rock created deep inside the Earth’s crust, contains it. But what about regular people with no knowledge about diamonds?

Someone who knows a lot about diamonds will find everything in this answer. But for regular people, we did our best to clear everything out!

However, when people look for an answer to one question, many readers come up with new questions that need to be answered, which in this case are what diamonds are, why and how they are formed in kimberlite, and what the process of their mining.

Learn More: How Long Does A Diamond Take To Form And Grow?