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7 steps to buying the perfect diamond

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The options can seem overwhelming,  but you don't have to be a professional jeweller to buy the perfect diamond! Here are the key steps for you to follow to help you on your diamond-buying journey!

Loose diamonds
Loose diamonds

1. Set a budget

Before shopping for a diamond, you should always have a budget in mind. If you choose a loose diamond and a ring setting, you may want a separate budget for each. 

You might hear guidance that you should spend anything from one month's salary to three months' salary on an engagement ring, but we think this is poor advice. In our view, you should look to spend an amount that is both affordable for you and enough to secure a ring that you will be happy to propose with.

Your budget may need to be larger for custom engagement rings as you will have to pay for design and customisation in addition to the standard costs of the diamond and setting.

At Ingle & Rhode, we offer finished rings, bespoke designs, and build-your-own rings to fit your budget. 

2. Understand the 4Cs

The 4Cs of diamond size and quality were developed by the Gemological Institute of America (GIA) in 1940 and are recognised and used universally across the jewellery industry worldwide.


You will typically hear the size of a diamond expressed in terms of carats. Carats are a unit of weight, with one carat equal to one-fifth of a gram. One-hundredth of a carat is called a point, so fifty points, for example, is the same as half a carat.

It is worth noting that different diamonds of the same carat weight can look superficially larger or smaller than other diamonds of the same weight, depending on their shape. This is because we tend to judge the size of diamonds by looking down on them from above, so a "shallower" diamond with a greater "spread" will appear larger than a "deeper" diamond with a smaller "spread". This often makes an oval diamond look bigger than a round diamond of the same carat weight, for example. 

A larger diamond will tend to cost much more than a smaller one of similar quality - a 1ct diamond will typically cost much more than double the price of a 0.5ct stone. You will also notice that prices tend to increase at the most popular weights such as 0.5ct, 0.7ct, 1ct and so on. If you can find a diamond you like just below one of these weights, you may get a bargain!

Very confusingly, the term 'carat' or 'karat' is used separately to describe the purity of gold. For example, 24ct gold is pure gold, whereas 18ct gold is 75% pure.  


Diamond colour refers to the yellow or brown tone found in most diamonds. The GIA created a colour scale to grade a diamond's different levels of colour saturation.


Colour is graded from D (the best, completely colourless) down to Z (severely discoloured). Diamonds of G colour or better typically look very white or colourless, but from H colour and below, you may start to notice some colouration to the untrained eye. Diamonds can also come in 'fancy colours', most commonly yellow, and these are graded on a different scale: 'Fancy Light, Fancy, Fancy Intense, Fancy Vivid' and so on.


All diamonds, whether natural or lab-grown, contain inclusions. These are flaws or imperfections in their crystal structure created during every diamond's formation. However, while all diamonds have inclusions, some diamond inclusions are only able to be seen under magnification. The GIA Clarity Scale ranks the overall prominence of inclusions in a diamond.

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Many clients are interested to know how far down the scale they can go while still expecting the diamond to appear flawless to the naked eye. The answer is that a stone graded VS2 or better will usually be "eye clean". Any stone graded SI2 or lower certainly won't be. Stones graded SI1 (Slightly Included) may or may not be eye clean - sometimes they are clean when viewed from above, as they will be when set in a ring, but not from other angles. If you are considering a diamond graded SI1 or below, you should check it carefully before deciding.


A diamond's cut refers to how it has been faceted and polished. The term is confusing because it is used to describe the shape of a diamond (e.g. round brilliant cut vs cushion cut), but in the case of the 4Cs, we are referring to the cut grades diamonds are given. Even more confusingly, round brilliant cut diamonds are given a separate grade for each of cut, polish and symmetry. In contrast, all other shapes are given only polish and symmetry grades (so they don't even have a cut grade, strictly speaking!).

diamond cut guide
GIA Diamond Cut Grades

The highest GIA grade is Excellent, followed by Very Good, then Good, then Fair. Stones below Fair are not graded.

Some other gemological labs (IGI, for example) have Ideal as their top cut grade, above Excellent.

Note that diamonds with a top cut grade will reflect and refract more light and sparkle more than those with lower cut grades.

3. Choose the shape

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A round brilliant cut diamond is the most popular diamond shape. It's also one of the most expensive due to its ability to have exact symmetry as an Excellent cut diamond. Fancy shapes (shapes besides round) don't have official cut grades on a GIA grading report. In addition to being the most expensive diamond shape, its face-up size is one of the smallest. Elongated fancy shapes such as emerald and oval cut diamonds look superficially larger than a round diamond of the same carat weight.

Aside from the visual size and price, the type of diamond cut affects the light performance of your stone. Emerald cut diamonds and Asscher cut diamonds have stepped faceting rather than brilliant faceting, meaning they refract less and reflect more light. This, in turn, means they sparkle less but instead produce more flashes of white light.

4. Choose the setting

Your ring setting is your chance to inject your unique style into your engagement ring. Some people choose the diamond before the setting, while others do the opposite.

While your initial instinct may be to pick your favourite ring setting within your budget, it should not be a decision made in haste. There are other factors to consider aside from personal taste and budget.

You should consider the ring setting you want in relation to your lifestyle. If you work in an office, a high-profile cathedral setting should be fine, but this type of ring setting may not be ideal for someone in the medical field.  

Low-profile ring settings are better for those with active lifestyles. However, if you've fallen in love with a diamond ring with a higher-set diamond, don't let that deter you. You'll just need to be selective about when, where, and how you protect the ring while wearing it.

5. Choose the precious metal

Gold and platinum are the most popular precious metals used to make fine jewellery. Sterling silver is not hard-wearing or strong enough for fine jewellery and requires more upkeep as it tarnishes, which isn't something you want in your bridal set. 

Gold purity is measured in carats (or karats in the US). Gold carats are different from diamond carats. Most retailers sell engagement rings and wedding bands crafted in 9ct or 18ct gold. 

Pure gold is too soft to be used for jewellery, so it needs to be mixed with other metals to strengthen it for daily wear. Pure gold is 24ct. Rings crafted in 18ct gold are 18 parts gold and six parts other metals. 

The metals alloyed with gold have a direct effect on its colour. White gold jewellery is gold that has been alloyed with white metals. It is finished off with rhodium, which gives white gold jewellery its silvery-white appearance. This is the most popular ring metal colour, but the rhodium will need to be reapplied over time. 

If gold has been alloyed with more copper, the colour will turn from its traditional yellow to a copper-coloured metal called rose gold or pink gold. Overall, the colour of gold doesn't significantly impact price, but the gold carat does. 

Platinum is a white metal we offer our customers looking for a more robust metal for their ring setting. Platinum is more durable than gold and does not need to be replated like white gold does. 

Platinum has a higher density than gold, making it heavier. Some may like the extra weight of a platinum ring, but others may not. Engagement rings crafted in platinum are usually more expensive than in gold. 

Stack of diamond eternity rings

6. Compare with other similar diamonds

Often, customers find the diamond they want is beyond the budget they would like to spend. If you find yourself in that predicament, you should compare your diamond to others with the same or similar grades. Often it is possible to find two very similar diamonds with quite different prices! If you have any concerns about why one might be less expensive than another, we'd be delighted to give you our expert advice.

7. Make your purchase!

You should have an idea about how you want to purchase your diamond. Most people like to pay by debit or credit card, but others prefer bank transfer or a payment plan. 

At Ingle & Rhode, we offer ten months interest-free credit through Novuna Personal Finance for UK customers. You can find out more here.

We offer free shipping worldwide. For UK customers, we use Royal Mail, and for other countries, we use FedEx. 

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Should I buy a natural or lab grown diamond?

Interest in lab grown diamonds has increased dramatically over the last few years. Both lab grown diamonds and natural diamonds are great options. They have the same physical, chemical, and optical properties. 

Lab grown diamonds are real diamonds created in a lab. The laboratory environment recreates the heat and pressure conditions that created diamonds naturally. 

A lab grown diamond can be the best option if you are on a strict budget. Lab grown diamonds can be significantly less expensive than mined diamonds of the same grades. 

Alternatively, many are drawn to the romance of a natural diamond formed by Mother Nature. Though diamonds may seem available in abundance, the majority of diamond rough mined is not gem-quality. You hold a unique treasure gifted by the earth. 

There are different reasons for choosing a lab grown diamond over a natural diamond or vice versa. You should weigh up all the pros and cons before making your purchase. 

If you'd like to know more about lab grown diamonds vs natural diamonds, you can contact our jewellery experts today. 

What should I check before buying a diamond?

You should avoid purchasing a loose diamond without a grading report from a reputable laboratory. The grading report provides independent assurance of the carat weight and quality of the diamond. All the loose diamonds at Ingle & Rhode are GIA or IGI-certified.

Conflict or blood diamonds are a big concern among many jewellery buyers. If you want to ensure that a diamond has been ethically-sourced, ask the jeweller whether they can trace it back to the country of origin. Many jewellers will refer to the Kimberley Process, but unfortunately, this cannot be relied upon, which is why at Ingle & Rhode, we only offer diamonds that can be traced back to ethical sources.

Is clarity or cut more important?

The 4Cs allow you to choose a diamond according to your priorities. For some, clarity is of higher importance, and they may compromise on the cut grade to fit their budget. Another person may choose the best cut grade and compromise on clarity. 

Neither is more important, and we recommend a balanced approach. It is a mistake to focus on just one aspect of the 4Cs.

Which of the 4Cs is the most important when buying a diamond?

None of the 4Cs is more important than the others in isolation, and priorities vary from one person to another. For some people, getting the biggest diamond they can for their money means they will be happy to compromise somewhat on quality, such as colour, clarity and cut.
For others, colour is very important, but they might be prepared to compromise on clarity or cut. Others would prefer to compromise on colour but not clarity.


A lot of thought needs to go into choosing the perfect diamond for your engagement ring. The carat weight, colour, clarity and cut should all be carefully considered when weighing up your options, not to mention the shape of the diamond, your choice of precious metal, and the style of the setting!

Our diamond experts at Ingle & Rhode will be delighted to help you work through all the options to help you identify your perfect diamond.

David Rhode
Together with Tim Ingle, David created Ingle & Rhode to offer a better alternative to the traditional luxury brands. Since 2007, we’ve provided our customers with genuinely ethical engagement rings, wedding rings and fine jewellery – free from conflict diamonds, dirty gold and child labour. With more than 16 years experience in the jewellery industry, David has deep expertise in diamonds, gemstones and jewellery design and manufacturing.