The Birth of a Diamond: Lots of Pressure!

When we see the finished product– a magnificent diamond ring or a beautiful diamond bracelet, it seems unthinkable that those diamonds are made of carbon.  Another product made of carbon, coal, is so different from diamonds that it makes sense to wonder:  how does carbon turn into a diamond?  Time for a history lesson …

The Journey to Become a Diamond

The carbon that eventually turns into a diamond starts out near the surface of the Earth.  Rocks in the Earth’s upper mantle containing carbon melt due to temperature changes, and the carbon seeps down deeper into the Earth.  When temperatures rise at different levels in the Earth’s mantle, the carbon keeps melting down and traveling deeper down.  The carbon makes quite a journey to reach conditions where diamonds can be formed– around 90 miles below the surface of the Earth!  This is just the beginning of the journey for carbon atoms to become diamonds.

What happens next in the journey to becoming a diamond depends on temperature and pressure conditions.  The ideal temperature for forming diamonds is 2000 degrees Fahrenheit.  This high temperature must combine with extreme pressure in order to create the right conditions for turning carbon into diamonds.  If the temperature or pressure deviates, the carbon will not transform into a diamond.

With such a small margin for error, you can be sure only specific places have the heat and pressure necessary for forming diamonds.  The areas deep in the Earth where carbon crystallizes into diamonds are located below continental plates.  But the diamond is still 90 miles below the surface of the Earth.  The journey has just begun.

The Journey to the Surface

Continental plates are not only the site of ideal conditions to form diamonds, they are also the site of many volcanoes.  Some diamonds “hitch a ride” to the surface of the Earth in volcanic eruptions.  Beneath a volcano are deep pipes, typically containing a blue rock called kimberlite.  When a volcano erupts, the kimberlite travels up the pipes and carries the diamonds with it.  The diamonds and the kimberlite may end up on the surface, washed away by streams, or buried in sediment.  Snow and rain may also carry diamonds away from a volcanic eruption and deposit them elsewhere until the diamonds are found.

Besides kimberlite pipes, natural diamonds are also found in alluvial deposits, a fancy name given when diamonds are found in river beds.
The term placer deposit is also used.

Some diamonds do not make it all the way to the surface and therefore require diamond mining.  The kimberlite pipes are found, studied and then excavated.

What countries do diamonds come from? There are 23 diamond producing countries in total.  See how many you can guess.

When you realize a Diamond takes many, many years to form and then travels miles and miles to the surface .. you can better appreciate this precious stone.  During this process, diamonds take on unique properties, diamond inclusions and blemishes, which make every stone unique.  So not only do you better appreciate what it takes to form a diamond, you know that no matter which one you choose, it is one of a kind, just like you.

Conflict Free Diamonds

No matter how they are formed, the process of mining and in turn selling a diamond can be big business.  The sale any stone known as a conflict diamond or a blood diamond is very serious issue and before you buy you should learn about it.  The simple definition  is any diamond used to fuel conflict and civil wars in Africa.  The Kimberley Process was set up to prevent this issue.  The only way to know if you stone is conflict free, is to buy from a company that offer’s a guarantee, as outlined by the Kimberley Process.  Read Mazal Diamond’s Conflict Free Guarantee and tour the Mazal Diamond Factory.  Be an informed shopper!

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