Your centre stone is the heart of your engagement ring. It's a reflection of your personal style, lifestyle, and the way you want your ring to look and feel for years to come.
Whether you're just beginning your engagement ring journey or refining your final design, understanding the key considerations can help you choose your perfect centre stone with confidence.
Gemstone Type
One of the most considered decisions you'll make is choosing between moissanite and a lab-grown diamond.
Our Signature Moissanite is the perfect choice for somebody who desires the highest quality diamond alternative, that is ethical and attainable. Moissanite is known for its exceptional brilliance and fire, offering a more accessible price point that allows clients to indulge in a larger carat size, without exceeding a reasonable budget.
A laboratory diamond is chemically, physically and optically the same as a mined diamond. They are one and the same - real diamonds. A lab grown diamond, however, is created above ground sustainably, with advanced technology mimicking the natural growth process of a mined diamond.
Both options are heirloom quality. The right choice ultimately comes down to your personal priorities, whether that's maximising size, selecting a more “traditional” diamond, or finding the best balance between quality and budget. Learn more about our gemstones.
Shape
The shape of your centre stone is one of the most defining features of your engagement ring. From oval and emerald to marquise and round, each shape creates a distinct look and influences the overall aesthetic of your ring.
While it's natural to have favourites based on what you've seen online, trying on different shapes is one of the most valuable parts of the design process. A shape you love in photos may feel completely different on your hand, while an unexpected option may become your favourite.
The goal is to choose a shape that feels authentically you.
AT TMC Fine Jewellers, the oval cut continues to be one of the most sought-after shapes, appreciated for its soft, elongated proportions and ability to maximise perceived size. However, trends come and go, and should always come second to personal preference. The key to creating a piece you will love forever is choosing a shape that feels undeniable yours.

Size
Carat size is often one of the most commonly considered aspects of an engagement ring, but it's only one part of the overall picture.
The ideal size depends on personal preference, hand proportions and the design of the setting itself. A well-balanced gemstone size often feels more impactful than simply choosing the largest possible stone.
At TMC Fine Jewellers, many clients naturally gravitate towards centre stones between 2 and 3 carats, with sizes ranging from 1.75ct to 3.5ct representing the majority of engagement ring designs. Rather than focusing solely on carat weight, we encourage you to consider how the stone sits on the hand, how it reflects light, and how it complements the overall design.
It's also important to remember that the most beautiful gemstone isn't always the biggest. Cut quality plays a significant role in how a diamond performs, influencing its brilliance, sparkle and overall presence. A beautifully cut diamond can often appear more striking than a larger stone with poorer proportions.
At TMC Fine Jewellers, we carefully source laboratory diamonds that meet strict quality standards, including Excellent cut, polish and symmetry grades. This ensures every diamond is selected not only for your requested size, but for its ability to maximise light performance and visual impact.
Ultimately, the right size is the one that feels balanced, suits your lifestyle and reflects your personal style. The goal isn't simply choosing a larger stone, but finding the size that feels right for you. Learn more about The 4C's.
Setting Style
When choosing your engagement ring setting, there are two key considerations to keep in mind: your lifestyle and your aesthetic preferences. A design that you will love for decades to come often achieves a balance between both, creating a ring that not only looks beautiful, but feels effortless to wear every day.
Your lifestyle should play an important role in the design of your ring. If you lead an active lifestyle or simply prefer a more practical everyday piece, a low set design may be worth considering. Our Low Set Signature Basket Setting is intentionally designed to sit close to the finger, holding your gemstone close, and reducing the likelihood of the ring catching on clothing or other surfaces.
Certain gemstone shapes may also benefit from additional protection. Shapes with pointed edges, such as marquise and pear cuts, are often secured with protective prongs at the tips, helping to safeguard these more delicate areas from everyday wear. A beautiful engagement ring should not only look incredible, but also suit the way you live.
The setting style also plays a significant role in the overall look and feel of your engagement ring. Whether your style leans classic, contemporary or somewhere in between, the setting helps define the character of the piece.
When designing your forever ring, it is important to keep balance in mind. Start with a setting you genuinely love, then allow the centre stone to remain the focal point. Often, the most timeless designs are those that embrace restraint, favouring thoughtful designs choices over excess detail. Remember, your wedding ring will eventually become part of the overall look, naturally adding another element, and adding character to your wedding stack. Discover our Signature Range.

Budget
Establishing a budget early in the process can help guide your centre stone selection and ensure you're focusing on the options that best align with your priorities.
Several factors contribute to the overall investment of an engagement ring. The most significant is often your choice of centre stone, including whether you select moissanite or a lab-grown diamond. If choosing a lab-grown diamond, the carat size, colour and clarity you select will also influence the final price.
Depending on the shape and faceting of your chosen lab-grown diamond, certain characteristics may become more important than others. For example, emerald cut diamonds feature large, open facets that can make inclusions more visible to the naked eye. For this reason, you may choose to prioritise a higher clarity grade, such as VS2 or above, over a larger carat size.
In contrast, brilliant-cut shapes such as oval lab-grown diamonds are designed to maximise sparkle and can naturally disguise minor inclusions more effectively. This may allow you to prioritise carat size while still maintaining a beautiful overall appearance.
Understanding how different diamond shapes interact with colour, clarity and light performance can help you allocate your budget where it will have the greatest visual impact. Ultimately, there is no right or wrong budget. The most important thing is choosing a centre stone that feels meaningful, balanced and uniquely yours.
Finding Your Forever Stone
At TMC Fine Jewellers, every engagement ring is thoughtfully crafted to celebrate your story.
Whether you're selecting a design from our Signature Range or creating a custom piece, our experienced team will guide you through every step of the process, helping you choose a centre stone that feels uniquely yours.
Proudly based in Australia, we are committed to exceptional craftsmanship, ethical innovation and creating engagement rings designed to be treasured for a lifetime.
Explore our Signature Range or get in touch with our team to begin your journey.