Do Diamonds Retain Pressure When They Surface from Deep Underground? Exploring the Science Behind the Migration

The Journey of Diamonds

Diamonds are one of the world’s most precious and sought-after gems. They are formed deep in the Earth’s mantle, typically at depths of 140-190 kilometers below the surface. The process of diamond formation occurs under extreme heat and pressure, causing carbon atoms to crystallize into the hard, transparent gemstone we know as a diamond.

Over millions of years, geological forces such as volcanic eruptions and tectonic activity can bring diamonds closer to the surface. As diamonds move closer to the surface, they undergo a process known as “exhumation,” in which they are gradually released from the high-pressure environment of the Earth’s mantle and move into the lower-pressure environment of the Earth’s crust and surface.

Retention of Pressure in Diamonds

The question remains, when diamonds “migrate” from deep underground to the surface, do they maintain pressure inside when there is no pressure outside? The answer is yes, diamonds can maintain pressure inside even when they reach the surface.

Researchers have found that diamonds exhumed from deep within the Earth’s mantle contain tiny pockets of gas created by the high-pressure environment in which the diamonds were formed. These gas pockets typically consist of nitrogen, hydrogen and other trace elements.
When diamonds are brought to the surface, the pressure outside the diamond decreases, but the pressure inside the diamond remains the same. This causes the gas pockets inside the diamond to expand, which can create internal stresses and even cause the diamond to crack.

The role of inclusions

Inclusions are tiny imperfections that are sometimes found in diamonds. They can contain things like small crystals, minerals, or other materials that were present when the diamond was formed. Inclusions can also contain pockets of gas.

Researchers have found that diamonds with inclusions are more likely to retain pressure inside them when they reach the Earth’s surface. This is because the inclusions create a barrier that prevents the gas pockets from expanding too quickly. Inclusions can also help stabilize the diamond’s structure, which can prevent cracking or other damage.

The implications for diamond mining

The fact that diamonds can retain internal pressure even when they reach the Earth’s surface has important implications for diamond mining. When diamonds are mined, they are usually brought to the surface quickly, which can cause the gas pockets within the diamond to expand rapidly and create internal stresses.
To prevent this, diamond miners often use a process known as “degassing,” in which the diamonds are heated to a high temperature and then slowly cooled. This process helps to release the gas pockets within the diamond in a controlled manner, which can prevent cracking or other damage.

In conclusion, diamonds are fascinating gems that are formed deep within the Earth’s mantle and can migrate to the surface over millions of years. When diamonds are brought to the surface, they can retain pressure inside, even when there is no pressure outside. This can cause internal stress and even cracking, but the presence of inclusions can help stabilize the diamond’s structure. The implications of this phenomenon for diamond mining are significant, and the degassing process is an important tool in preventing damage to valuable gemstones.

FAQs

1. How are diamonds formed and where are they found?

Diamonds are formed deep in the Earth’s mantle, typically at depths of 140-190 kilometers below the surface. They are formed from carbon atoms that crystallize under extreme heat and pressure over millions of years. Diamonds are found in various locations around the world, including Africa, Russia, Canada, and Australia.

2. What is the process of exhumation?

Exhumation is the process by which diamonds are brought closer to the Earth’s surface. This can occur through geological forces such as volcanic eruptions and tectonic activity. As diamonds move closer to the surface, they are gradually released from the high-pressure environment of the Earth’s mantle and move towards the lower pressure environment of the Earth’s crust and surface.

3. Can diamonds retain pressure inside when they reach the Earth’s surface?

Yes, diamonds can retain pressure inside even when they reach the Earth’s surface. This is because diamonds that are exhumed from deep within the Earth’s mantle contain tiny pockets of gas, which are formed by the high-pressure environment in which the diamonds are created.

4. Why do diamonds with inclusions have a better chance of retaining pressure inside?

Diamonds with inclusions are more likely to retain pressure inside when they reach the Earth’s surface because the inclusions create a barrier that prevents the gas pockets from expanding too quickly. Inclusions can also help to stabilize the diamond’s structure, which can prevent cracking or other damage.

5. How do diamond miners prevent damage to diamonds during the mining process?

To prevent damage to diamonds during the mining process, diamond miners often use a process known as “degassing.” This involves heating the diamonds to a high temperature and then slowly cooling them down. This process helps to release the gas pockets within the diamond in a controlled manner, which can prevent cracking or other damage.

6. What are the implications of diamonds retaining pressure inside when they surface?

The fact that diamonds can retain pressure inside when they surface has important implications for diamond mining. Diamond miners need to be aware of the potential for internal stress and cracking when diamonds are brought to the surface. The degassing process is an important tool for preventing damage to valuable gemstones.

7. How does the presence of gas pockets within diamonds affect their value?

The presence of gas pockets within diamonds can affect their value, as they can cause internal stress and cracking. However, some diamonds with unique and rare gas inclusions may actually be more valuable to collectors and investors. Ultimately, the value of a diamond is determined by a variety of factors, including its size, clarity, color, and cut.