Ruby Vs Spinel: Best Tips to Distinguish These Gemstones

Ruby vs Spinel: What’s the difference? These gemstones might look alike but differ in origins, colours, physical properties, and market value. Historically, people often misidentified spinel as ruby due to their similar appearance. A famous example is the 'Black Prince's Ruby' in the British Crown Jewels, which was later revealed actually to be a spinel. Spinel was historically mistaken for ruby due to its vibrant red hue, closely resembling the prized colour of rubies. This guide will help you understand these distinctions and confidently identify and choose between them. Historically, spinel was highly regarded in Europe, often mistaken for rubies and popular among royalty, frequently used in regal jewelry. Spinel was highly prized during the medieval period and favoured by the nobility for creating regal jewelry. In 1783, spinel was officially distinguished as a separate mineral species from ruby.

• Rubies and spinels have distinct origins. Rubies form in metamorphic environments and emerge from metamorphic and magmatic processes.

• The colour differentiation is notable. Ruby is usually bright red, while spinels come in a wider range of colours, making proper identification challenging.

• Clarity, chemical composition, and market value significantly influence the desirability and pricing of rubies and spinels. Due to their rarity, rubies generally command higher prices. Ruby has a hardness rating of 9 on the Mohs scale, making it one of the hardest gemstones.

Understanding the Origins of Ruby and Spinel

Rubies typically form in metamorphic environments like marble and schist, with Burma (now Myanmar) being the most historically renowned source. Natural rubies, especially those that are untreated and possess exceptional colour, are highly valued and rare compared to treated rubies and other gemstones like spinels. The most valuable rubies are those that are a deep, rich red colour with excellent clarity and very few inclusions. High-quality ruby prices continue to rise due to increasing difficulty in finding stones of this quality.

Spinels can form from both metamorphic and magmatic processes. They were first discovered in ancient Sri Lanka. Spinel is commonly found in limestones that have undergone metamorphism and in ultramafic rocks such as peridotite. Their distinct characteristics and value are shaped by their geological and historical contexts. Spinel is typically highly transparent, allowing for easy spotting of blemishes or inclusions within the gemstone. Additionally, spinel has a vitreous lustre and is known for its excellent transparency. Tools and instruments, such as a dichroscope and a jeweller’s loupe, can help distinguish between rubies and spinel.

Geological Formation

Rubies are primarily found in metamorphic rocks such as marble and schist. The presence of chromium causes their vivid red colour.

Classified as a distinct mineral species by Jean-Baptiste Louis Romé de L'Isle in 1783, spinels are sourced from regions like Myanmar, Sri Lanka, Vietnam, and Tanzania. The unique geological conditions in these areas enhance their formation, value, and allure.

Historical Context

Ancient civilizations like the Egyptians and Romans highly valued rubies and spinels for their protective powers. The Black Prince's Ruby, a famous spinel mistaken for a ruby, highlights the historical confusion between these two gemstones. The name refers to the optical doubling effect in rubies, which often led to misidentifications. Vibrant red spinels were frequently referred to as ‘ruby spinel' due to their striking resemblance to rubies.

Frequent misidentification of spinels as rubies and sapphires earned them the nickname ‘the great imposter.' These anecdotes underscore the enduring allure and mystery of these gemstones.

Colour Differences Between Ruby and Spinel

One of the most striking differences between ruby and spinel is colour. Rubies are primarily bright red, with shades ranging from pinkish-red to deep blood-red, often called ‘pigeon’s blood red.’ The finest rubies exhibit this deep red hue, commonly known as 'pigeon blood' red, which is highly sought after and commands the highest market prices. Ruby's strong red fluorescence gives it a beautiful glow under certain lighting conditions.

Conversely, spinels come in a broader colour range, including red, blue, pink, orange, and deep black. Intense reds and pinks are particularly prominent. Spinels are typically highly transparent, allowing easy inspection for blemishes or inclusions.

These colour characteristics help differentiate the two gemstones. How light interacts with these gems affects their colour and visual appearance, with rubies and spinels exhibiting distinct refractive properties.

Primary Colors

Chromium largely influences the vivid red colour of rubies, giving them prized deep blood-red and pinkish-red hues. Spinels can exhibit a variety of colours, including red, blue, pink, purple, and black, making them versatile for different jewelry designs.

This diversity in colour can make differentiating between red spinel and ruby challenging without professional training.

Secondary Hues and Inclusions

Due to different trace elements, secondary hues in rubies can range from purplish to orangey-reds. They also have unique internal features called ‘fingerprints' that distinguish them from spinels, which generally lack such inclusions.

Identifying these secondary hues and visible inclusions is essential for gemologists and collectors to accurately differentiate between rubies and spinels.

Physical and Chemical Properties of Different Trace Elements

Rubies and spinels’ physical and chemical properties offer a scientific basis for their distinctiveness. Both are durable, but rubies are slightly harder and more scratch-resistant. On the other hand, synthetic rubies are generally clearer and lack the inclusions found in natural rubies, affecting their perceived quality. Rubies have a refractive index ranging from 1.76 to 1.78, contributing to their brilliance. Spinel, with a refractive index ranging from 1.712 to 1.736, also exhibits significant brilliance, making it a captivating choice for jewelry.

The unique chemical compositions and crystal structures of these gemstones further distinguish them. However, exposure to harsh chemicals or abrasive materials can lead to scratches and chips on rubies and spinels, emphasizing the importance of proper care.

Hardness and Durability

With a Mohs hardness rating of 9, rubies are highly resistant to scratches, making them ideal for everyday wear. Spinels, rated 8, are also durable and suitable for high-contact jewelry due to their lack of cleavage. Spinel has a hardness of 8 on the Mohs hardness scale.

These properties make both rubies and spinels excellent choices for durable gemstone jewelry.

Crystal Structure and Composition

Ruby is a variety of the mineral corundum, formed in metamorphic and igneous rocks. Rubies are composed of aluminum oxide (Al2O3) with chromium impurities, whereas spinels, which consist of magnesium and aluminum, have a chemical formula of MgAl2O4. Rubies form under high-pressure and high-temperature conditions, distinguishing their crystal structure and composition. The word 'ruby' comes from the Latin word 'ruber,' meaning red. Ruby is one of the four precious gemstones, along with diamonds, emeralds, and sapphires.

Spinel is a magnesium aluminum oxide mineral formed in metamorphic and igneous rocks.

These crystal structure and composition differences are key to distinguishing these two gemstones.

Clarity and Inclusions

Clarity and inclusions significantly impact the appearance and value of rubies and spinels. As one of the four precious gemstones, rubies have been valued and culturally significant throughout the ages. Rubies typically contain more inclusions than spinels, leading to a less uniform appearance. The visibility and type of inclusions can greatly affect the value and desirability of these gemstones.

Typical Inclusions

Rubies often show liquid inclusions, such as fingerprints and discoid fractures, which affect their clarity. Conversely, spinels can display unique optical features, such as pleochroism and two-phase inclusions. Due to their octahedral crystal growth, spinels sometimes resemble human fingerprints. Spinels can display pleochroism, showing different colours at different angles, further enhancing their visual appeal and making them distinct from rubies.

These inclusions help gemologists and collectors identify and authenticate these gemstones.

Impact on Value

Inclusions can significantly lower the value of rubies by affecting their clarity and aesthetic appeal. While still important, inclusions in spinels may have less impact on pricing than rubies. High-quality gemstones with fewer visible inclusions are more sought after and command higher market prices.

Market Value and Pricing

Several factors, including rarity, size, and treatment, influence the market value and pricing of rubies and spinels. Ruby jewelry is highly appealing as a classic and luxurious choice, with ruby's longstanding dominance in the jewelry market due to its beauty, durability, and high value. Rubies are the rarest of the major gemstones, significantly impacting their market value and leading to higher prices than spinels. Ruby has long dominated the market as a symbol of luxury jewelry, especially Burmese rubies that can fetch astronomical prices. Ruby has been featured in numerous high-end jewelry pieces and auctions throughout history, further cementing its status as a symbol of luxury and prestige. While some spinels can be quite valuable, most red spinels are considerably less expensive than ruby of comparable quality. In recent years, demand for spinel has increased, leading to a rise in its prices for certain types.

Understanding these factors is crucial for investing in these beautiful gemstones.

Factors Affecting High Prices

The origin of a ruby is crucial for its valuation, with Burmese rubies being the most sought-after for their quality. High-quality spinels without visible inclusions are significantly more valuable than those with flaws.

High-quality rubies with deep red colour and excellent clarity are incredibly valuable. The most valuable rubies display a deep red hue, often called 'pigeon blood' red. Additionally, untreated rubies command higher prices than heat-treated rubies.

Market Trends

High-quality rubies continue to see increasing demand as investment pieces. Both rubies and spinels are highly sought after in high-end jewelry markets, appealing to collectors for their unique colours and rarity.

Spinels are generally more abundant and affordable than rubies of comparable quality, making them popular among jewelry enthusiasts.

Astrological and Symbolic Significance

The astrological and symbolic significance of rubies and spinels adds emotional and cultural value to these stones. Rubies symbolize love and passion, making them meaningful engagement ring choices. Rubies are the traditional birthstone for July, while spinel was added as an official birthstone in 2016 for August.

Spinels also hold significant astrological and symbolic meanings, enhancing their appeal.

Astrological Benefits

In Hinduism, rubies are seen as the ‘king of precious stones' associated with powerful rulers and protection from harm. Spinels, linked to zodiac signs like Aries, Scorpio, Taurus, and Sagittarius, are believed to promote emotional stability and creativity.

These astrological benefits make these gemstones popular among those seeking spiritual and emotional balance.

Symbolism and Cultural Importance

For centuries, rubies have been culturally significant. They are often associated with royalty and used in royal jewelry to symbolize power and wealth. Rubies represent passion, love, and courage and are believed to enhance vitality, leadership, and success. Ruby has been cherished for centuries, holding a prominent place in royal jewelry across global empires. Rubies were often believed to possess magical powers and offered protection against evil spirits in ancient civilizations.

Linked to the planet Mars, red spinels are believed to amplify martial energy and are increasingly recognized for their beauty and rarity.

Popular Uses in Jewelry

Rubies and spinels are frequently used in high-end jewelry, including engagement rings, fine jewelry, and collectibles. Their vibrant colours and durability make them popular among jewelry enthusiasts.

Engagement Rings

Rubies are increasingly chosen for engagement rings for their vibrant red hue and symbolic meaning of love. Spinels offer a unique and affordable alternative, making them popular for those seeking a durable and beautiful gemstone for their ring.

Both gemstones are frequently used in statement pieces due to their captivating colours, including the ruby gemstone.

Fine Jewelry and Collectibles

Historically, rubies and spinels have adorned royal jewelry, symbolizing power and wealth. Both are highly sought after for high-end jewelry pieces, and spinels are often set in various precious metals to enhance their visual value.

Their striking colours and unique designs make these gemstones a frequent choice for engagement rings.

In conclusion, understanding the differences between ruby and spinel gemstones involves examining their origins, colour characteristics, physical and chemical properties, clarity, market value, and symbolic significance. Both gemstones hold unique appeal, with rubies being more valuable and spinels offering a more affordable yet equally beautiful alternative. These stunning gemstones continue to captivate and inspire, whether for investment or personal adornment.

Is the black Prince's ruby a stone called a spinel?

Yes, the Black Prince's Ruby is a red spinel, not a true ruby. It weighs 170 carats and is prominently featured in the Imperial State Crown of the United Kingdom.

Is spinel precious or semiprecious?

Spinel is traditionally classified as a semi-precious gem, but its beauty and increasing popularity elevate its status in the gem market. Its diverse colours and bright, vitreous lustre contribute to its appeal.

What are the primary colours of rubies and spinels?

Rubies are primarily vivid red, ranging from pinkish-red to deep blood-red, while spinels showcase a broader spectrum, including red, blue, pink, orange, and black.

How do the origins of rubies and spinels affect their value?

The origin of rubies greatly enhances their value, particularly with Burmese rubies being the most prized. Meanwhile, high-quality spinels free of visible inclusions also command a higher market price.

What are the typical inclusions found in rubies and spinels?

Rubies typically contain liquid inclusions like fingerprints and discoid fractures, whereas spinels may exhibit distinctive optical features such as pleochroism and two-phase inclusions. Understanding these features enhances appreciation for the uniqueness of these gemstones.