Diamonds are often considered the most coveted and valuable gemstones in the world. While the classic white diamond remains the most popular choice for jewellery, diamonds can come in various colours, from pink to red, green to purple, and even black. Among the coloured diamonds, yellow and blue diamonds stand out for their unique and stunning hues.

But what exactly sets yellow and blue diamonds apart, and how are they different from the more common white diamonds?

In this blog, we will explore the fascinating world of yellow and blue diamonds, from their geological origins to their unique properties and characteristics.

Geological Origins Of Yellow And Blue Diamonds

Yellow And Blue Diamonds

When understanding the geological origins of yellow and blue diamonds, it's essential to consider the key factors that give these precious stones their unique colours. 

Here are some of the most important points to keep in mind:

Formation In The Earth's Mantle

Diamonds, in general, are formed under extremely high pressure and temperature conditions deep in the Earth's mantle. The carbon atoms are tightly packed, crystallizing over time to form diamonds. The geological processes that give rise to diamonds can take millions or even billions of years.

Nitrogen Impurities And Yellow Diamonds

Yellow diamonds get their hue from impurities of nitrogen atoms in the carbon lattice structure. These impurities can trap light in a specific way that gives the stone its yellow colour. The exact shade of yellow can vary depending on the amount and distribution of nitrogen in the diamond.

Boron Impurities And Blue Diamonds

Blue diamonds are much rarer than yellow diamonds, and they get their colour from impurities of boron atoms in the carbon lattice structure. Boron absorbs red, yellow, and green light, which means that blue light is reflected in our eyes, giving the diamond its striking blue hue. The shade of blue can vary from a pale blue to a deep, almost navy blue colour.

Geological Events

The geological events that bring diamonds closer to the Earth's surface are crucial for their discovery and extraction. Some diamonds, including yellow diamonds, can be found in riverbeds, where alluvial deposits have accumulated over time. Other diamonds, such as blue diamonds, are often found in volcanic pipes that reach the surface.

Properties And Characteristics Of Yellow And Blue Diamonds

As we mentioned earlier, yellow diamonds get their colour from nitrogen impurities. However, not all yellow diamonds are the same. The intensity of the yellow hue can vary from faint to vivid, and the colour can be affected by other impurities in the diamond, such as hydrogen or boron. Yellow diamonds are also known for their high clarity and brightness, making them popular for engagement rings and other jewellery.

On the other hand, blue diamonds are incredibly rare and highly coveted. The colour of blue diamonds can range from pale sky blue to deep navy blue, and the exact shade of blue can be affected by the presence of other elements in the diamond, such as hydrogen or nitrogen. Blue diamonds also have a unique luminescence that dazzles them, especially in sunlight.

Another fascinating characteristic of blue diamonds is their ability to conduct electricity. This is due to the presence of boron in the diamond, which gives it semiconducting properties. In fact, blue diamonds are used in a variety of high-tech applications, such as electronic components and superconductors.

Uses Of Yellow And Blue Diamonds In Jewelry And Other Luxury Items

Diamonds have long been cherished for their exquisite beauty and unique characteristics, and yellow and blue diamonds are no exception. Let's look closer at how these stunning gems are used in jewellery and other luxury items, and why they are so highly prized.

Yellow Diamonds In Jewelry

Yellow Diamonds In Jewelry

Yellow diamonds are a popular choice for engagement rings and other jewellery pieces. Their warm and vibrant colour adds a touch of sunshine and elegance to any design. Yellow diamonds can be cut into shapes, such as round, cushion, pear, or radiant, to showcase their brilliance and fire. They are often used as centre stones, complemented by white diamonds or other gemstones in intricate settings to create stunning and eye-catching jewellery pieces.

One of the most famous yellow diamonds is the Tiffany Yellow Diamond. It was discovered in South Africa in the late 19th century, the Tiffany Yellow Diamond weighs over 128 carats and is considered one of the largest yellow diamonds ever found. It has been set in several designs over the years, including a necklace worn by Audrey Hepburn in a publicity shoot for the film "Breakfast at Tiffany's."

Blue Diamonds In Jewelry

Blue diamonds are some of the rarest and most valuable diamonds in the world, and they are highly sought after for their mesmerizing colour. Blue diamond jewellery is often considered a symbol of luxury and prestige. Blue diamonds can be used in various jewellery designs, from elegant and sophisticated pieces to more modern and artistic creations.

Blue diamonds are typically set in white gold or platinum to enhance their vivid blue hue. They are often accented with white diamonds or other coloured gemstones to create a captivating contrast.

One famous example of a blue diamond in jewellery is The Blue Moon Diamond. It weighs over 12 carats and was sold at auction in 2015 for a record-breaking $48.5 million. The Blue Moon Diamond is known for its stunning, vivid blue colour and has been set in several different designs over the years, including a ring worn by Hong Kong billionaire Joseph Lau's daughter.

Other Uses Of Yellow And Blue Diamonds

In addition to jewellery, yellow and blue diamonds are also used in other luxury items. High-end watches, cufflinks, brooches, and other accessories often feature yellow and blue diamonds as focal points or accent stones, adding a touch of glamour and sophistication. These rare and valuable diamonds are also used in custom-designed pieces, such as tiaras and crowns for special occasions or royal events, showcasing their exceptional beauty and prestige.

Wrapping Up

In conclusion, yellow and blue diamonds are two of the rarest and most valuable types of diamonds in the world. They are highly sought-after for their unique colours, which are caused by different impurities and structural irregularities within the diamond crystal. Yellow diamonds are typically coloured by nitrogen impurities, while the presence of boron colours blue diamonds.

Despite their colour and origin differences, yellow and blue diamonds share many common properties and characteristics, such as their hardness, lustre, and brilliance. They are also highly prized for their beauty and rarity and are often used in high-end jewellery and luxury items.


Are yellow and blue diamonds more expensive than white diamonds?

Generally, yes. Yellow and blue diamonds are rarer and more valuable than white diamonds due to their unique colours and limited availability.

How are yellow and blue diamonds graded?

Yellow and blue diamonds are graded using the same 4 Cs criteria as all other diamonds: colour, clarity, cut, and carat weight. However, the grading scales used for yellow and blue diamonds differ from those used for white diamonds.

Can yellow and blue diamonds be used for engagement rings?

Yes, yellow and blue diamonds can be used for engagement rings, offering a unique and eye-catching alternative to traditional white diamonds. Many couples choose coloured diamonds, including yellow and blue, for their engagement rings to express their individuality and personal style.