August 04, 2024

An Expert's Guide to Choosing Gemstones

For centuries, humans have been captivated by the vibrant colours, natural brilliance, and profound symbolism of gemstones. From ancient civilisations that revered them as tokens of power and divine favour to modern-day aficionados who appreciate their beauty and rarity, gemstones hold a timeless allure. The process of buying or selecting a gemstone, however, can be daunting, given the myriad options available and all the factors influencing both their value and suitability for different purposes.

Whether you're a seasoned collector or a first-time buyer, we take joy in sharing in our passion and expertise to support you in making informed decisions when it comes to purchasing or selecting the perfect precious stone. We'll get into the intricacies of gemstone selection, from understanding value factors to navigating the myriad of options safely and ethically. This guide can serve as a foundation of knowledge as you embark on the journey of acquiring a unique gemstone that will be cherished for a lifetime.

Selecting Gemstones in Context: From Everyday Wear to Special Occasions

Before you decide on the perfect gemstone, an important consideration is where and how often you will be wearing the gemstone - whether part of a uniquely designed engagement ring or personalised piece of fine jewellery. Think about why you want the gemstone to begin with. The reason being, that some stones are perfect for daily wear, while others are better suited for special occasions due to their durability and susceptibility to damage.

Selecting Gemstones for Engagement Rings and Wedding Bands

We treasure engagement rings and wedding bands as symbols of eternal commitment, and more often than not they are worn daily (although we always advise the most treasured pieces are taken off where there is a risk of abrasion - think gardening, gym, sports, even washing up… this will reduce the risk of damage). Therefore durability is important. Classics like diamonds, sapphires, and rubies are excellent choices for these rings due to their hardness and resistance to scratching. These stones can withstand the rigours of daily wear and remain stunning through many years or generations.

Versatile Gemstones for Daily Wear Jewellery

For jewellery pieces that will be worn frequently, such as bracelets, earrings, and necklaces, diamonds, sapphires, and rubies also work wonderfully, but there are many other worthy and meaningful gemstones. Aquamarine, with its understated and elegant light blues is hardy enough for most daily wear pieces but perhaps best suited for earrings or necklaces where there is less risk of abrasion. If you are drawn to emerald’s deep greens but need something less brittle, Tsavorite garnet is an excellent choice. Tanzanite has rich, royal blues/purple and is also versatile and hardy - though never use an ultrasonic to clean them. Tourmaline is a gem that comes in a variety of beautiful colours, sometimes even multiple colours in one piece, and is also well-suited for regular wear.

Statement Stones for Special Occasions and Haute Couture

Gemstones like opals, emeralds, and tanzanites, with their unique and striking appearances, make excellent choices for statement pieces meant for special occasions. Padparadscha Sapphires are the rarest of sapphires and an alternative take on the usual sapphire colouration - it’s bound to make a statement. Pearls (an organic gem) are generally white, also radiate exceptional colours fit for a unique piece - even something like the purple-hued kunzite, which is perhaps not as well-known but still holds absolute unique beauty. However, due to their relative softness and susceptibility to damage, these are best reserved for less frequent wear.

Considering Lifestyle and Practicality in Gemstone Choices

Your lifestyle plays a significant role in determining the best gemstone for you. If you lead an active lifestyle or work with your hands frequently, opt for harder stones like diamonds or sapphires. Conversely, if you seek a gemstone for occasional wear or special events, you can explore a broader range of options, including more delicate stones.

While no piece of jewellery is indestructible, even if it contains only diamonds, the utmost care must be taken to maintain it for as long as you can. This means, whatever gemstone it includes, regular cleaning with gentle soap and water to remove buildup, and we recommend at least an annual clean by professionals to keep your pieces beautiful for years to come.

Understanding Gemstone Classifications

While all gemstones have inherent value, gemstones are broadly classified into precious and semi-precious stones, each category offering a wide array of options to suit different tastes and budgets.

Defining Precious Stones: Diamonds, Rubies, Sapphires, and Emeralds

Precious stones are typically rarer and more valuable than their semi-precious counterparts, hence the naming convention. Diamonds, rubies, sapphires, and emeralds all fall into this category, each with unique characteristics that make them highly desirable. Their value stems from the way they are formed, how challenging they are to source or mine, and how rare they are in nature. 

Precious stones all have fascinating and different ways of forming, giving them their own appeal, story and beauty. This may have an impact on choosing one, for example, diamonds are the hardest substance on earth and take millions of years and immense pressure to form. Oftentimes, the gem’s backstory complements your reason for choosing it, making it an even more personal choice.

The Vast World of Semi-Precious Stones: From Amethyst to Zircon

You have probably heard of many of these semi-precious stones; amethyst, agate, aquamarine, aventurine, citrine, garnet, topaz, turquoise, tourmaline, tiger’s eye, moonstone, goshenite, jade, malachite, lapis lazuli, obsidian, peridot, quartz, zircon - there are hundreds from all over the world. Many come in different varieties and they all span the rainbow of dazzling colours. As with precious gemstones, they also have their own symbolism, cultural meaning, history, unique formation and monetary value. Whether a gemstone is more valuable to you personally will make the difference when choosing, be it precious or semi-precious.

Most of the pieces created in our jewellery are considered to be “precious stones” however from time to time we will seek to incorporate semi precious stones where it relates to a deeper personal meaning or desirable aesthetic.

Organic Gems: Pearls, Amber, and Coral

Organic gems, such as pearls, amber, and coral, are derived from living organisms and have been used in jewellery for thousands of years. Pearls are made over long periods of time inside oysters or mussels as a defence against outside irritants. Amber is hardened tree resin that takes more than 40,000 years to form and is loved for its warm orange hues. 

Coral is also a living sea organism which forms over long periods, and has been prized for thousands of years. Due to their crucial role in the ecosystem, harvesting or use of coral has to be sustainable and come from ethical sources that don’t deplete the natural resources or affect the climate. These unique qualities make organic gems cherished and valued for their natural beauty and origins, adding to their meaning. 

When it comes to organic gemstones - Pearls are our preference. They are beautiful, formed over multiple years and clean the ocean… what is not to like?

Lab-Grown Gemstones: Artificial Alternatives

Lab-grown gemstones are created in controlled environments and offer a cost-effective alternative to natural stones. They are created through a process that replicates the natural conditions in which gemstones are formed, imitating the chemical, physical, and optical properties of natural gemstones. Gems that can be lab-grown include diamonds, coloured diamonds, sapphires, rubies, spinel, emeralds, alexandrite, moissanite, and opal. 

As one of the only B-Corp certified jewellers, Blackacre chooses to work exclusively with ethically sourced and sustainable natural diamonds. Their inherent beauty reflects the awe of the natural world and they are deeply associated with romance and luxury - values we strive to embody in our designs. We strive to ensure that our natural diamonds are sourced ethically and sustainably, giving you peace of mind when choosing the perfect piece.

We are slightly old fashioned and believe that there is a charm and romance to a wondrous stone created by mother nature - something that cannot be replicated by a large scale factory…

The Four Cs of Gemstone Grading: Colour, Clarity, Cut, and Carat Weight

The value and beauty of gemstones are determined by many factors, but the so-called Four Cs: Cut, Colour, Clarity, and Carat weight are perhaps the most simplistic and digestible way of gaining a basic understanding of any given gemstone. Understanding these factors is crucial when selecting a gemstone.

• Cut: The cut of a gemstone refers to how well it has been shaped and faceted. A well-cut stone will reflect light beautifully, enhancing its brilliance and sparkle.
• Colour: The colour of a gemstone is perhaps its most defining characteristic. The most desirable stones have rich, vibrant hues with even colour distribution.
• Clarity: Clarity measures the presence of inclusions or blemishes within a gemstone. Stones with higher clarity grades are rarer and more valuable.
• Carat Weight: Carat weight measures the size of a gemstone. Larger stones are generally more valuable, but it's essential to balance size with quality.

When it comes to precious gemstones - we often find that they are cut a little deeper than white diamonds of the equivalent shape and size. The reason being is that a deeper stone will increase the saturation of colour - and in the context of coloured stones, this often makes the gemstone more desirable. 

We use the analogy of tissue paper - if you have one layer of blue tissue paper it is relatively pale and translucent. Yet when you hold 5 pieces of tissue paper together or fold the same piece over itself - the blue colour becomes darker/stronger and more saturated.

The Importance of Colour in Gemstone Selection

Colour significantly influences a gemstone's value and appeal. In gemstones like sapphires and emeralds, the intensity and saturation of colour play a crucial role in their desirability and price. The colour is important not just because of personal preference or symbolism, but also because of how the colours come about. 

The gemstones used in blue sapphire rings, for instance, get their colour from the presence of iron and titanium in the crystal lattice of corundum. Different shades also depend on where they are found. Historically, the finest sapphires, sourced from Kashmir, India, and Myanmar, possess a sought-after "velvety" quality due to microscopic inclusions within the crystals. Ultimately, while the colour affects a gemstone’s grading, its value to you is what is important when choosing.

In the most simplistic of analogies - historically the more saturated/stronger colours have been the most sought after. However in recent times, as a heightened sense of individualism becomes more important, the paler more watery colours have also come to the fore.

Clarity Grades and Their Impact on Beauty and Price

Clarity grades range from flawless to included, with flawless stones being exceedingly rare and valuable. However, some inclusions can add character to a gemstone and do not necessarily detract from its beauty. For example, silk and needle-like inclusions are thin, thread-like features within a gemstone that can create a soft, silky sheen or a star-like effect when cut in specific ways. 

Among all gemstones, within diamonds the clarity grade is often considered more prominently because their inclusions affect light refraction and carat weight.  These inclusions often enhance a gem's beauty, contributing to phenomena such as asterism in star sapphires.

Carat Weight: Balancing Size with Quality

While larger stones are often more impressive, it's essential to balance size with the other C’s - cut, colour, and clarity - to ensure you select a high-quality gemstone. The carat determines its value, yes, but it’s also an important personal choice and considers the intention and meaning behind the chosen gemstone and carat. We would always opt for a higher quality stone over size - however it is also important to adopt a pragmatic view and consider the details that can be seen to the eye.

Beyond the Four Cs: Additional Value Factors

Several additional factors contribute to a gemstone's value, including rarity, origin, market trends, and treatments.

The Role of Rarity in Gemstone Pricing

Rarity significantly impacts a gemstone's price. Rare stones like Paraiba tourmaline or Kashmir sapphire command high prices due to their limited availability. It is worth noting that gemstones such as these are far rarer than natural white diamonds…

How Origin Affects a Stone's Desirability and Cost

The geographic origin of a gemstone significantly influences its value and appeal. For example, Burmese rubies are highly prized for their intense red colour and rarity, often commanding premium prices. However we take great care in sourcing stones of such origin now due to the the geopolitical situation in country - consequently such colours are best sought from antique pieces.

Similarly, Colombian emeralds are renowned for their vivid green hue and clarity, making them extremely desirable. The specific characteristics of gemstones from different regions, such as colour saturation and historical significance, contribute to their overall desirability and cost. Understanding a gemstone's origin can thus provide valuable insights into its potential value and allure.

Understanding Gemstone Treatments and Their Effect on Price

Gemstone treatments, such as heat treatment or irradiation, can significantly enhance a stone's colour and clarity, making it more visually appealing. However, these enhancements can also impact a gemstone's value. Treated stones are generally priced lower than their natural, untreated counterparts due to their modified nature. Understanding the type of treatment a gemstone has undergone is crucial for assessing its true worth, as treatments can affect not only the stone's appearance but also its long-term durability and resale value. 

Heating is a generally accepted practice which the vast majority of gemstones will go through - resulting in a permanent change to the gems crystal structure by mimicking the conditions under which the stone was formed.

Certification and Authentication

Certifications provide assurance of a gemstone's quality and authenticity, making them crucial when purchasing valuable stones. Whilst the vast majority of diamonds are certified (this has no comment on their value, origin or price) gemstones only tend to be certified when they are significant specimens

The Importance of Gemstone Certificates

A gemstone certificate from a reputable laboratory verifies the stone's characteristics, such as cut, colour, clarity, and carat weight, providing confidence in your purchase. Typically, certification is reserved for specimens that form part of a specific collection or are exceptionally highly valued - most gemstones aren’t certified, but if one is, you know it is of the utmost purity and quality. A gemstone need not be certified to be considered precious, it just provides additional peace of mind.

Reputable Gemological Laboratories and Their Grading Standards

There are several renowned gemological laboratories around the world, such as the Gemological Institute of America (GIA), the American Gem Society (AGS), The Gemological Association of Great Britain (GEM-A), and the International Gemological Institute (IGI). They all follow strict grading standards, ensuring the accuracy and reliability of their certificates.

How to Read and Interpret a Gemstone Certificate

Understanding how to read a gemstone certificate is essential. Look for details on the Four Cs, any treatments the stone has undergone, and the laboratory's grading standards.

Beware of Counterfeit Certifications and Self-Issued Documents

Be cautious of counterfeit certifications and self-issued documents from sellers. Always verify the authenticity of a certificate with the issuing laboratory.

Responsible Gemstone Sourcing

Ethical and sustainable practices are becoming increasingly important in the gemstone industry. Knowing where and how your gemstones are sourced can impact your purchasing decisions.

Understanding Conflict-Free Gemstones: Conflict-free gemstones are those mined without funding armed conflict or human rights abuses. It's crucial to seek out conflict-free stones to ensure your purchase does not contribute to unethical practices.

The Importance of Traceability in the Gemstone Supply Chain: Traceability ensures that gemstones are sourced responsibly, with transparency throughout the supply chain. This practice helps prevent unethical mining and trading activities.

Environmental Considerations in Gemstone Mining: Gemstone mining can have significant environmental impacts. Opting for stones sourced from environmentally responsible mines helps reduce the negative effects on ecosystems and communities.

Fair Trade Practices in the Gemstone Industry: Fair trade practices ensure that miners and workers receive fair wages and work in safe conditions. Supporting fair trade gemstones promotes ethical practices in the industry.

Popular Gemstone Choices

Certain gemstones have timeless appeal and are popular choices for various types of jewellery.

Classic Diamonds: Diamonds remain the most popular choice for engagement rings due to their brilliance, durability, and timeless elegance. A classic diamond engagement ring is a symbol of everlasting love and commitment.

Sapphires (Including Blue and Green Varieties): Sapphires, known for their deep blue hue, are a regal alternative to diamonds. Engagement rings featuring green sapphires offer a unique and beautiful variation that is gaining popularity.

Emeralds: Emeralds, with their rich green colour, have been prized for centuries for their regal elegance. They make stunning centre stones for engagement rings and other fine jewellery.

Rubies: Rubies, with their deep red colour, symbolise passion and love. They are durable and make an excellent choice for both engagement rings and statement pieces.

Unconventional Choices: Paraiba Tourmalines, Alexandrites, and Coloured Diamonds are unconventional choices for jewellery due to their rarity and unique characteristics. Paraiba Tourmalines, only discovered in the late 1980s, are prized for their neon blue and green hues caused by copper. Alexandrites are renowned for their remarkable colour-change property, appearing green in daylight and red under incandescent light. Coloured Diamonds, especially natural ones, are rare and sought-after, with their vibrant hues resulting from unique impurities or structural anomalies. These distinctive features make them appealing for bespoke and high-end jewellery, but less common in mainstream collections.

How to Find The Perfect Gemstone For You

Navigating the gemstone marketplace or scouring the internet for reliable and legitimate sources and deals can be a veritable minefield. While online resources can be informative, the expertise, passion and personalised service of a reputable, jeweller cannot be beaten. We recommend you take the following steps into consideration when looking for the right gemstone for you.

• First and foremost, choose a jeweller with a standout reputation, history and knowledge. Besides your own preferences and intentions, this is the most important place to begin for an honest, informed and hands-on gemstone selection experience.
• Insist the jeweller you have chosen has proper diamond certification and ethical sourcing practices for your gemstones. We are immensely proud of our B Corp Certification but are also members of the National Association of Jewellers (NAJ). 
• The vast majority of the diamonds we use are certified by the Gemological Institute of America (GIA) with a number of our gemstones certified by more specialist local labs.
• Additionally, the majority of our suppliers are members of the Responsible Jewellery Council, and our diamonds are guaranteed conflict-free by the Kimberley Process Certification Scheme (KPCS). 
• Make it personal - book an appointment to discuss your needs and custom designs with your jeweller in person. Choosing the right gemstone is a personal decision and should not be left to chance or done over the internet. The right jeweller will discuss your needs and design options in-depth and you can assess the quality of the gemstones and jewellery yourself.
• In simple - find someone that shares your values and cares about supporting you find the perfect gemstone (and consequently designing a perfect piece)

We hope that with the knowledge gained from this guide, you can now begin to navigate the journey of choosing the right gemstone for you or approach our team to support you. Remember that each gemstone tells a unique story - one that you'll continue as its new custodian.

Explore our curated collection of ethically sourced, certified gemstones or book a consultation at Blackacre. We take great joy in bringing designs to life and one of our team of expert designers, gemologists or jewellers will be delighted to help you in any way we can.