Black diamonds, also known as carbonado diamonds, are a rare and unique form of natural diamond. Unlike traditional diamonds which are transparent and colorless, black diamonds have a dark black or gray coloration that makes them stand out. But what exactly makes black diamonds so special and desirable? Here we will explore what gives black diamonds their distinctive dark color, what makes them different from other diamonds, and the special properties and meanings associated with these exotic gemstones.
What Causes the Black Color in Black Diamonds?
Black diamonds get their dark color from the presence of microscopic black inclusions distributed throughout the crystal structure. These black inclusions are made up of either graphite or sulfides. The high concentration and even distribution of these black particles is what gives black diamonds their opaque, black appearance.
In contrast, traditional diamonds get their colorlessness and transparency from having very low levels of inclusions. So it is the abundance of black impurities that makes black diamonds stand apart.
Some key things to know about the inclusions in black diamonds:
– They are naturally occurring, not artificial treatments. The black color is 100% natural.
– The black particles are distributed evenly throughout the crystal, not just surface level. This gives an opaque black look when viewed from any angle.
– The inclusions are microscopic – generally less than 1mm. You need a loupe or microscope to see individual particles.
– Diamond clarity grading does not apply. Black diamonds are graded on darkness of color, not clarity.
What Makes Black Diamonds Different From Other Diamonds?
There are a few key ways that black diamonds differ from other diamond varieties:
– **Color** – Obviously the black color is the most distinguishing feature. Traditional white diamonds transmit white light. Black diamonds absorb most light, transmitting only a black or gray hue.
– **Clarity** – Black diamonds are opaque, not transparent. They never achieve the flawless clarity of the highest grade white diamonds.
– **Rarity** – Only a very small fraction of the diamonds mined worldwide are black diamonds, making them more rare. Most rough diamonds are traditional transparent whites.
– **Source** – Black diamonds come from limited geographic sources. Major deposits are found in Brazil and Central Africa.
– **Structure** – Black diamonds tend to have a more porous, less dense crystalline structure than other diamonds. This gives them a distinctive “soft” lustre.
– **Strength** – Black diamonds are not quite as hard or strong as transparent diamond crystals due to their more porous structure. But they still rank high in hardness and durability.
– **Value** – Large high quality black diamonds can achieve high prices. But in general black diamonds sell for less per carat than rare fancy color transparent diamonds.
So in summary, the black color, rarity, and unique gemological properties really set black diamonds apart from other diamond varieties.
Natural Origins of Black Diamonds
As mentioned above, the black color of these diamonds comes from natural inclusions present when the diamonds were first formed deep underground. But just how do these rare black diamonds form naturally?
Black diamonds are believed to originate under one of two different geologic scenarios:
**1. Rapid Cooling of Diamond Material**
This theory states that black diamonds were formed from rapid cooling of carbon material within the Earth. Normally diamonds crystallize slowly over billions of years. But rapid cooling allowed tiny particles of black impurities to get trapped evenly inside the crystal structure.
**2. Direct Conversion from Graphite Material**
The second theory states that black diamonds actually formed directly from graphite material subjected to high pressure deep in the Earth. The graphite did not have time to fully convert to crystalline diamond, leaving behind black graphite inclusions.
Either way, these natural processes resulted in large concentrations of black impurities becoming entrapped within the diamonds as they formed. This created the opaque, black coloration we see in these rare diamond stones.
Unique Properties of Black Diamonds
The unusual way that black diamonds form gives them some unique properties compared to other diamond varieties:
– **Soft Lustre** – Black diamonds have a distinctive soft, velvety luster unlike the brilliant flashes of white diamonds. This comes from a more porous, less dense crystal structure.
– **Conductivity** – They tend to be better conductors of heat and electricity than white diamonds due to their more porous structure.
– **Strength** – Black diamonds rank about 10 on the Mohs scale of hardness, compared to a perfect 10 for colorless diamonds. This lower hardness comes from a more irregular crystal lattice.
– **Toughness** – Their porous structure makes black diamonds more prone to fracturing or cleaving if struck. So they are not as tough as crystalline white diamonds.
– **Acoustics** – The porous structure also gives black diamonds higher sound absorption. This dampens acoustic resonance which reduces musical ringing tones.
So while black diamonds fall short of white diamonds in terms of hardness, strength, and brilliance, they have their own set of intriguing properties due to their unique formation history.
Where are Black Diamonds Mined?
Natural black diamonds are exceptionally rare, found in only a few locations worldwide. Unlike common white diamonds which are mined globally, black diamond deposits are confined to just a couple ancient geological formations:
– **Brazil** – This is the world’s leading source, producing over 90% of global black diamond production. They are found in alluvial deposits in the states of Bahia and Minas Gerais.
– **Central African Republic** – Second most important source, with deposits along the Sugba River. Black diamond crystals here can reach over 10 carats.
– **Angola/DRC** – Additional black diamond deposits found in riverbed gravels along the Congo River system.
– **Australia** – Small black diamond finds along the Palmer River in Queensland. But very limited quantities.
– **Venezuela/Guyana** – Recent discoveries of black diamond deposits in the Roraima region of South America. Still under exploration.
So Brazil dominates as the premier source for natural black diamonds. The supply is still quite limited, keeping black diamonds rare.
Meaning & Symbolism of Black Diamonds
In addition to being rare and beautiful gems, black diamonds carry special meanings and symbolism:
– **Elegance** – Their dark color and soft lustre gives black diamonds an air of elegance and sophistication. The epitome of understated luxury.
– **Boldness** – Black diamonds make a bold fashion statement, for those wanting something more edgy and unique than plain white diamonds.
– **Rebellion** – Historically, black diamonds were considered cursed or undesirable. Wearing black diamond jewelry shows a rebellious spirit.
– **Anti-materialistic** – Black diamonds shun the traditional beliefs that white diamonds are highest. Their black color embracing a more anti-materialistic mindset.
– **Protection** – Black is seen as a grounding, protective color. Black diamond jewelery is thought to provide protection from negative energy.
– **Power** – The color black also evokes a sense of personal power, strength, and resilience. Black diamond wearers project personal power.
– **Mystery** – The exotic black color adds an air of mystery and intrigue. Black diamonds represent the mysterious side of nature.
Black Diamond Grading Factors
Like other diamonds, black diamonds are graded according to the 4Cs – Cut, Clarity, Color and Carat:
– **Cut** – Cut quality is assessed the same way as white diamonds – rating symmetry, polish and proportions. Top grades maximize black diamond’s soft lustre.
– **Clarity** – Since black diamonds are opaque, normal clarity grading is not used. Clarity refers to evenness of black color distribution.
– **Color** – Color grading assesses darkness of black color. Totally black stones are most desirable. Partial greys are lower quality.
– **Carat** – Carat weight measures the black diamond’s mass. Bigger carat black diamonds are exponentially more rare and valuable.
So cut and color are most important for black diamonds. Carat size also heavily influences their market value.
Unique Cut Shapes for Black Diamonds
Black diamonds are cut into many classical and unique shapes:
– **Round** – The iconic round brilliant is the most popular cut, displaying a soft, velvety black hue.
– **Cushion** – Cushion cuts retain the rounded outline but with square-ish facets. Very elegant in black diamonds.
– **Pear** – The teardrop pear shape works well in black diamonds. It has a delicate, romantic vibe.
– **Oval** – Oval cuts elongate the outline of the black diamond for a contemporary look.
– **Marquise** – Long marquise shapes maximize carat weight. Their tapering points beautifully display the black color.
– **Princess** – The sharp edges of princess cut black diamonds project striking sophistication.
– **Radiant** – Squarish radiant cuts combine step-cut and brilliant facets for a bold black effect.
Many other cuts like heart, trillion, baguette, emerald are also used in stylish black diamond jewelry. The choice comes down to personal style and design taste.
Black Diamond Engagement Rings & Jewelry
Due to their mystique and symbolism, black diamonds make highly distinctive jewelry pieces:
– **Black Diamond Engagement Rings** – A black diamond center stone makes for a unique nontraditional engagement ring. Accented with white diamonds, the contrast is eye-catching.
– **Black Diamond Pendants** – A round or pear black diamond pendant necklace is sophisticated and glamorous. The black diamond is set in white gold or platinum for maximum contrast.
– **Black Diamond Earrings** – For bold black diamond earrings, black princess cuts work well. Suspending elongated marquise or pear black diamonds from the ears has an elegant effect.
– **Black Diamond Bracelets** – Multiple small black diamonds are used in tennis or line bracelets. Single larger black diamonds make striking bangle or cuff bracelets.
– **Black Diamond Rings** – Stackable black diamond eternity bands are a popular ring choice. Black diamonds combined with onyx or hematite in the same ring has a dramatic gothic effect.
So black diamonds give jewelry far more edge, intrigue, and artistic flair than standard white diamond pieces. Black diamonds embody bold personal style.
|Round||Iconic, displays soft lustre|
|Cushion||Elegant, rounded square outline|
|Pear||Romantic, tear-drop silhouette|
|Oval||Contemporary, elongates outline|
|Marquise||Delicate shape, maximizes carat weight|
|Princess||Striking sophistication, sharp edges|
|Radiant||Bold, combines step and brilliant facets|
Precautions for Black Diamond Jewelry
Despite their resilience, care should be taken when wearing and storing black diamond jewelry:
– Avoid wearing black diamonds during rough, everyday activities. Their lower toughness makes them prone to knocks and blows.
– Take care to remove black diamond rings, earrings and bracelets before cleaning, gardening, exercising or other vigorous activities.
– Use a soft brush and mild soap solution to gently clean black diamonds. Avoid ultrasonic or steam cleaners which can damage their soft structure.
– Store black diamonds separately from other gems and diamonds. The darker color may transfer onto other jewelry if stored touching.
– Keep black diamonds away from chlorine, bleach or other chemicals which can potentially stain or damage the surface.
With some basic precautions, black diamonds can be worn and enjoyed for many years without damage. Their dark color requires a little extra care compared to tough white diamonds.
In the world of diamonds, black diamonds are an exceptionally rare and special member of the family. Their prized black color comes from microscopic inclusions formed through ancient geologic processes. Black diamonds have uniquely soft luster and velvety appearance unmatched by other diamonds. Mined in very limited quantities in Brazil and Africa, black diamonds are some of the most scarce diamond gems. Beyond their natural intrigue, black diamonds are embedded with special symbolism of sophistication, boldness and mystery. More than just striking jewelry, black diamonds embody elegance and personal spirit. So for those with distinctive and artistic taste, black diamonds are the ultimate choice.