If you plan to join the 75% of Australian men who buy their “special lady” a diamond engagement ring, you will want to pay close attention to the following advice. This is not something you want to get wrong. Not only are you about to part with a substantial amount of money (all women know the engagement-ring mantra about the fiancé waving goodbye to at least a month’s salary), but you are also about to purchase an object that will be a permanent symbol of the most important relationship of your life.

There are universally agreed rules on buying diamonds. Follow them, and you should avoid the pitfalls.

First, a geology lesson: diamonds are 99.95% pure crystallized carbon and can be extremely old – one to three billion years old. They are the hardest naturally occurring substance known and are formed beneath the Earth’s surface when crystals of diamond occur in volcano feed-pipes. When volcanoes erode down, they release diamonds from their feed-pipes into layers of gravel later mined. However, due to this natural process’s relative rarity, diamond mines are found in just a handful of sites around the world. In rough form, diamonds are shipped to the world’s cutting centres to be shaped and polished before being set as jewellery. The hardness, brilliance, and sparkle that emerges during this process transforms them into a girl’s best friend.

Now for a quick history lesson, as you may be curious to know where the fashion began. Legend dictates that in 1477, a lovestruck Austrian, Archduke Maximilian, came up with a gem of an idea: why not give Mary of Burgundy a diamond ring to celebrate their imminent engagement? He placed it on the third finger of her left hand – the finger believed by ancient Egyptians to have a vein that led straight to the heart. It is not known whether the marriage was a success, but you don’t need to worry about that.

The Four Cs

So now that you know why you are buying an engagement ring made with a diamond, you can familiarise yourself with the “Four Cs” – cut, colour, clarity and carat. All must be considered equally when comparing diamonds, but more than any other factor, according to Tiffany and Co, it is how the diamond is cut that will determine its defining characteristic.


As the only characteristic of a diamond not influenced by nature, the cut is open to mistakes and bad practices. Cut a diamond incorrectly, and the defining sparkle will be compromised. It is how the 57 or 58 facets (the tiny planes cut on the diamond’s surface) are angled and sized that dictate how light reflects and exits the diamond, an effect known as its “fire”. Make the cuts too deep or too shallow, and the diamond will be less brilliant.

The cut will also determine the shape of the diamond. The most common shape is the round cut, but others include the emerald, the pear, the marquise, the princess, the oval and the heart shape. Ask to see all of these shapes, if only in a picture, to make sure you have covered all your options.


The most valuable and rare colour is white, that is to say, colourless. Jewellers grade absolutely colourless diamonds with a “D”. The scale moves up to “Z” (don’t ask what happened to A, B and C) and, between these two extremes, diamonds will display subtle coloured tones. Diamonds with very strong and distinct colour are extremely rare and are called fancies.


Many people get unnecessarily hung up over the clarity of a diamond. Look into most diamonds with a jeweller’s loupe (magnifying eyeglass), and you will see small “inclusions”, also known as “nature’s fingerprints”. They look like small clouds or feathers but are usually invisible to the naked eye. Inclusions can affect the diamond’s fire, but they also make your diamond unique and shouldn’t always be seen as a fault. Why worry too much about something you can’t see, anyway? As long as the stone is graded SI1 (Slightly Included 1) or better (best and most expensive is IF, or Internally Flawless; worst is I3, or Imperfect 3), you should be all right.


The weight, and thus the size, of a diamond, is measured by carat. A carat is equal to 0.2gm, or 200mgm. A carat is divided into 100 smaller units called points. For example, three-quarters of a carat is 75 points. The average size of most engagement-ring diamonds is somewhere between one carat and half a carat. Do not confuse carats with karats, the unit of purity for gold.

Any reputable jeweller will know about the four Cs and be prepared to talk you through them all without prompt when displaying diamonds. But if you don’t wish to place your trust entirely in a jeweller, you should request a “cert stone” – a diamond that has been assessed, graded and coded with a laser by an independent gemological laboratory. The type of certificate is important, as not all are universally recognized. The most internationally recognized are issued by GIA (the Gemmological Institute of America). Other popular certificates include HRD, IGL, EGL and AGS (see Diamond Certificate Issuers, right). The fee for a grading certificate varies depending upon the carat of your diamond, but for exact prices, contact a specific laboratory. And do not be afraid of organizing your own certificate rather than accepting the jeweller’s recommendation.


The Right Weight for Your Ring

Choosing a gem for a ring is a very personal decision that depends on several factors. Understanding and prioritizing those considerations will help you choose the right carat weight. Keep the following tips in mind.

Carat Weight and Size

It’s important to remember that carats are a unit of weight, not a measurement of size. Depending on how it is cut, a one-carat gem may look much larger or smaller. Four Mine reports that a one-carat diamond with a round cut maybe 6.5 mm in diameter, but a princess cut diamond of the same weight is only 5.5 mm. Additionally, cuts may vary depending on the jeweller, with one-carat diamonds coming in in a variety of sizes.

Set Your Budget

There’s no set guideline about how much you should spend on an engagement ring, but you do need to determine your budget before you start shopping for a stone. All other factors being equal, larger carat weights are going to cost more. The number of carats a ring should be is the number of carats that fit comfortably in your budget.

Consider Finger Size

Another important consideration is the finger size of the person wearing the ring. If the bride-to-be has wide fingers, she may look gorgeous wearing a ring that’s two carats or more. However, if she has delicate hands, a large gem may look out of place on her finger.

Think About Setting

The carat weight of the gem is only one part of its perceived size in a ring. Side stones, halos, and other design elements can make a stone appear larger. Additionally, many engagement ring settings are made to accommodate a certain size of the gem. If you choose one that’s too large or too small, it won’t sit properly on the ring.

Practicality and Preference

A large gem can be lovely, but it’s not the ideal choice for everyone. If the person wearing it works with her hands or needs to avoid high profile gems for other reasons, a smaller stone may be a better option. Similarly, some people prefer the simplicity of a smaller stone. These factors are very important when considering the right gem size for you.

Tips for Buying an Engagement Ring

Not so long ago, choosing an engagement ring required just a few questions: princess or emerald cut? White gold or yellow? These days, there’s a lot more to consider when figuring out when, where, and how to buy an engagement ring. Here, the best tips for making this monumental purchase.

Don’t get caught up in a trend.

An engagement ring should be a timeless, classic symbol of your love that will last forever, so the goal should be to find the stone that is the perfect match for your future fiancé. Look at their current jewellery to see what would best suit his or her style. Are they gold or a platinum person? Do they wear statement jewellery or instead opt for minimal pieces? Take cues from their current style to inform how you pick the piece they’ll want to wear every day for the rest of their lives.

A stone doesn’t have to be perfect on paper.

Diamond experts often cite the “Four Cs” (aka colour, cut, clarity, and carat), but certificate grading should be just one of the many factors in your decision-making. You don’t need a D Flawless stone to create a beautiful ring. It’s better to judge a stone by the feeling it gives you rather than the GIA grading (diamonds are graded from D to Z by the Gemological Institute of America) is received. The grade can serve as a starting point, but should not be the sole determining factor.

Size matters only if you (or your future fiancé) think it matters.

Go big or go home shouldn’t be the mantra unless you think it’s the most important thing to your future spouse. In that case, weigh your options. Perhaps placing more of an emphasis on size and less on colour and clarity is worth considering.

Even those in the jewellery industry have noticed this trend. “I think there’s less pressure to have a showy ring now,” Jess Hannah, the founder of Los Angeles–based jewellery line J.Hannah says. “Now, the ring is more of an extension of someone’s personal style, and sometimes that means intentionally opting out of ‘bling.’ I love that women feel more empowered to go against the traditional jewellery store [mould] and find something that speaks to them on a personal level. It feels like a feminist choice.”

Know where the stone came from.

According to Page Neal, jewellery designer and co-founder of Bario Neal, clients appreciate jewellery with backstories especially when those backstories involve ethically sourced gems. Neal searches high and low for mines and suppliers who can prove their diamonds, metals, and gemstones have been sourced sustainably and are completely traceable from Mine to market. “I think people really want to know where their jewellery is coming from,” Neal says. “People really like that we go and search for stones for their custom pieces. We look for stones that are different and interesting and come back to discuss their options.” If you’re working with a jeweller like Neal, soak up every little detail to share with your future fiancé after you give her a ring.

The setting shouldn’t be an afterthought.

After you’ve fallen in love with a stone, the next step is figuring out what to put around it. “My fiancé collaborated with one of my best friends, Montana Coady, to design my ring,” explains wedding stylist Cynthia Smith of Cynthia Cook Brides. “Her advice was to think of the centre stone as a piece of artwork and the setting as the frame. You can be bold and do something different and unique, but it is important that the ring reflect the style of the person who will be wearing it.” Find an expert whom you trust, give them an idea of what you want, and let them guide you in the right direction.

Don’t be afraid to think outside the box and choose an entirely unique ring.

Millennials want everything they buy to feel special, and for a ring’s vibe to match up with their own. It’s becoming more common for women to eschew diamonds and traditional settings entirely and opt for something personal, unique and unexpected. “People are yearning for something different. They want something that feels ‘fashion’ and relevant, but also timeless—not basic, boring, or predictable. They come to us for a ring that’s unusual but still clean and sleek so it won’t go out of style,” says Azlee designer Baylee Zwart.

Consider working directly with a jeweller.

“Custom feels more special than just walking into a store and picking something,” Hannah explains. “Generally speaking, a lot of people now want something that walks the line between vintage and modern. It’s not so much about a big diamond anymore—they want quality oversize, or a unique shape, like a rose cut. And a lot of people are ditching diamonds altogether. I made a really beautiful ring with alexandrite, which is a colour-change stone that is greenish-blue in the daylight and purple in incandescent light. [Engagement rings] aren’t one size fits all anymore.”

Don’t go it alone.

Engagement ring shopping can be a daunting task—get by with a little help from your friends. Ask those who’ve gotten engaged for jeweller recommendations and call upon someone who knows you and your future spouse and whose taste you love and respect for their opinion regarding aesthetics. Nine times out of ten the person you’re buying for has an idea of what they want in their head and may have expressed it to a said friend (or added to a Pinterest board).

Don’t commit.

Unlike the matrimonial commitment, you’re hoping to make, try to avoid entering into a binding agreement with the jeweller. Worst-case scenario, if your intended hates what you’ve come up with, you should be able to exchange it for something else. You want your future spouse to love both you and the jewellery you buy forever.

It’s not about the price tag.

During the Depression, in a campaign that would’ve made Don Draper proud, De Beers’ advertising geniuses started running an ad pushing men to spend one month’s salary on a ring if they wanted to be “responsible.” By the 1980s, it jumped up to two months. These days, the rule of thumb that’s often referenced is that one should fork over at least three months’ salary when purchasing this piece of forever jewellery. This is all just clever marketing. The truth is there’s no exact science when it comes to how much to spend on an engagement ring, and some women prefer smaller, less expensive diamonds (or want to forego diamonds altogether). Some are going the vintage, or secondhand route (eBay’s ring market is up 58 per cent); and some are choosing a plain band à la Amanda Seyfried. Get the ring that’s perfect for the woman, not the ring whose price tag aligns with an arbitrary algorithm.


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