Birthstones | Posy Fine Jewellery Toronto

Sapphire and Ruby

Suzanne Crudden — Fri, 17 Jan 2025 23:07:51 +0000

Sapphire and Ruby: Iconic Gemstones

Are there any more iconic gemstones than sapphire and ruby? Excepting perhaps diamond and emerald, they are clearly among the most well known and prized gemstones. Rubies and sapphires are actually both varieties of the mineral corundum. This mineral is composed of aluminum oxide and what makes a gem either a sapphire or a ruby is slight variations in their chemical composition.

Here we’re going to explore where sapphire and ruby were first discovered and their history, their formation, what makes them different and some famous examples. But before we do that, here is a silly, little poem that we wrote to describe the difference between sapphire and ruby: Rubies are red, sapphires are blue. Except that’s not strictly true. Barring red, sapphires come in every hue!

Discovery and Historical Significance of Sapphire and Ruby

Corundum crystals were first discovered and prized in ancient India and Myanmar (formerly Burma). These regions have a long-standing reputation for producing some of the finest rubies and sapphires in the world and that continues to this day. Ancient civilizations valued these gems not only for their beauty but also for their perceived mystical properties. Rubies, in particular, were associated with power and protection, while sapphires symbolized wisdom and purity.

The highest quality sapphire and ruby came from South East Asia. For ruby the highest quality came from Myanmar (formerly Burma) and for sapphire the highest quality came from Kashmir. The mines where those standard setting gems came from have long since run out. But the material coming from this area is still of very high quality.

Another point of historical significance for sapphire and ruby is their inclusion on the traditional birthstone list. Rubies are the birthstone for the month of July and sapphires are the birthstone for the month of September.

Composition and Hardness of Sapphire and Ruby

Rubies and sapphires are both composed primarily of aluminum oxide (Al₂O₃). Their remarkable hardness, rated 9 on the Mohs scale, is second only to diamonds. This hardness makes them a great choice for jewellery you wear everyday such as an engagement ring. But sapphire and ruby are also great choices for any type of fine jewellery.

Defining Characteristics: Ruby vs. Sapphire

What Makes a Ruby?

A ruby is defined by its vibrant red color, which results from trace amounts of chromium. The intensity and hue of red can vary, but for a corundum crystal to be classified as a ruby, it must exhibit a dominant red color. When the red hue is not strong enough, the stone is classified as a pink sapphire instead. The boundary between pink sapphire and ruby can be subjective and varies in different markets.

The most prized shade of ruby is known as pigeon blood red (we know, gross). A true red ruby is one of the most expensive gemstones on the market, even more expensive than diamond. This is because a true red hue is very rare.

What Makes a Sapphire?

Any colour, except red, of the mineral corundum is classified as a sapphire. From the traditional blue to white, yellow, orange, pink, green and purple. If the material is more pinkish than red it will be classified as a sapphire. If the material is more red with a bit of pink it will be classified as a ruby.

The different colours of sapphire result from trace elements other than chromium present in the crystal structure. For instance, iron and titanium create blue sapphires, while iron alone can produce yellow and green hues.

Padparadscha Sapphire

One of the rarest and most coveted varieties of sapphire is the padparadscha, characterized by a pinkish-orange hue. The name “padparadscha” is derived from the Sinhalese word for lotus blossom, reflecting the gem’s distinctive color. These stones are predominantly found in Sri Lanka, with their unique colouration attributed to a mix of chromium and iron.

Famous Sapphires and Rubies

Legendary Gems

Throughout history, several rubies and sapphires have gained fame for their size, beauty, and historical significance. Among the most renowned rubies is the “Sunrise Ruby,” a 25.59-carat gem of exceptional colour and clarity, which set a world record at auction. The “Sunrise Ruby” is a perfect example of the prized ‘pigeon blood red’ colour.

For sapphires, the “Star of India” stands out. This massive, 563.35-carat star sapphire, housed in the American Museum of Natural History, is famed for its asterism. An asterism is a star-like phenomenon created by needle-like inclusions within the stone.

Another iconic sapphire is the “Logan Sapphire,” a 423-carat blue sapphire known for its deep, rich color. This gem, also on display at the Smithsonian Institution, is one of the largest faceted sapphires in the world.

Perhaps the most well known sapphire is the one that is set within Princess Diana’s and now Princess Catherine’s engagement ring. Although not exceptional in size, it is still without doubt a legendary stone.

Let’s sum up. What have we learned about sapphire and ruby?

they are actually just different colours of the same mineral
while ruby must always be red, sapphires are available in many different colours
they have been prized since ancient times
exceptional and rare examples are very valuable
with a hardness second only to diamond they are very suitable for everyday wear

If you have any other questions or if you would like to create your own piece of sapphire or ruby jewellery, we’d love to help! Please reach out to us or complete our quote request form.

The post Sapphire and Ruby first appeared on Posy Fine Jewellery Toronto.

What is Alexandrite?

Suzanne Crudden — Fri, 17 Jan 2025 20:35:33 +0000

If you’ve heard of Alexandrite at all, you probably know it as the birthstone for June. But, what is Alexandrite?

The short answer is that alexandrite is a colour change gemstone that changes from purple/red in indoor light to teal/green in outdoor light. But, in this article we’re going to explore alexandrite a bit deeper. We’ll answer the question of ‘what is alexandrite’ by looking at its origins, chemical make up, colour change properties, symbolism and rarity.

Origins and Discovery

Alexandrite was first discovered in the Ural Mountains of Russia in the early 19th century. The story goes that it was found on the birthday of the future Russian Tsar Alexander II in 1834. This led to the gemstone being named in his honour.

The Urals remained the primary source of alexandrite for many years because it was known for specimens with exceptional color-changing properties. Today alexandrite is also found in Brazil, Sri Lanka, and East Africa, particularly Tanzania and Zimbabwe.

The deposits in the Ural Mountains are now mostly depleted. Alexandrite that is known to have come from this area is highly sought after.

What is Alexandrite Made of?

Alexandrite is a variety of the mineral chrysoberyl, with the chemical formula BeAl2O4. It is the presence of chromium as a trace element that gives alexandrite its extraordinary colour-changing ability. Chrysoberyl itself is an oxide mineral, but the unique conditions required for alexandrite’s formation make it exceptionally rare.

Chemically, alexandrite is a variety of the mineral chrysoberyl with the formula BeAl₂O₄. The presence of chromium impurities is what gives alexandrite its distinctive colour-change property. While standard chrysoberyl is typically yellow to green and does not exhibit colour change, the chromium in alexandrite causes it to absorb light differently which causes the colour change phenomenon. This differentiates alexandrite from regular chrysoberyl both in appearance and value.

The Colour Change Magic of Alexandrite

What truly sets alexandrite apart from other gemstones is its remarkable ability to change colour depending on the light source. This colour change magic is due to the complex way alexandrite absorbs light.

Under natural daylight or florescent light, alexandrite appears green to bluish-green due to the high concentration of chromium. However, under incandescent or warm indoor light, it changes to a red to purplish-red hue. This dramatic colour change is a result of the gemstone’s complex crystal structure which affects how the stone absorbs and reflects different wavelengths of light.

The alexandrite gemstones in the halo of the ring below show the colour change phenomenon. The center stone is a sapphire and does not exhibit colour change.

Symbolic Meaning

Often referred to as “emerald by day, ruby by night,” alexandrite is believed to bring balance between the physical and spiritual worlds. It symbolizes joy, hope and wisdom, and is thought to enhance intuition and creativity. Alexandrite is also said to bring good luck and fortune to its wearer.

June’s Birthstone

In 1952, alexandrite was officially recognized as the birthstone for June, alongside pearls and moonstone. Its unique colour-changing ability and rarity make it a swoon-worthy choice for those born in this month.

Because pearls and moonstones are quite soft, alexandrite is often used in jewellery designs that require durability such as in a ring. When a jewellery design requires a facetted stone to match other facetted stones, such as in a family birthstone ring, alexandrite is also often chosen to represent June over a pearl.

What is Alexandrite Worth?

The rarity of alexandrite cannot be overstated. Alexandrite is one of the rarest gemstones in the world. Quality specimens, particularly those with a strong and distinct colour change, are incredibly scarce. The original Russian deposits are mostly depleted, which adds to the stone’s rarity and high value.

Modern sources, while producing beautiful gems, rarely match the quality of the original Urals stones. As a result, fine alexandrite is often more expensive than diamonds, particularly for stones that exhibit a vivid colour change and are free of inclusions. This rarity, combined with its unique optical properties, makes alexandrite one of the most valuable gemstones on the market.

Luckily, lab grown alexandrite is available at a much more reasonable price point. The lab grown variety also exhibits colour change and won’t break the bank.

Are you an Alexandrite Fan?

Alexandrite is definitely one of our favourite gemstones. If you’re as enchanted as we are with this unique gemstone we’d love to help you create your dream piece of alexandrite jewellery. You can request a quote for your idea or learn more about our process.

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