How To Choose A Diamond | Mitchel & Co

Diamond buyers guide

Buying a diamond should be a special experience. We’ll make sure that it is.

If you’re in the market for a loose diamond, whether it’s for an engagement ring or another special piece of jewellery, the first thing to remember is this – the primary reason to choose a particular stone is because you love it. Or the person you’re buying it for will love it.

At Mitchel & Co, we often get customers who come into the shop and are so consumed by the four Cs that they’ve forgotten they’re buying perhaps the most significant piece of jewellery they’ll ever purchase. Of course, the four Cs are important. Each can affect the value of your stone. But use them as a guide, not a shopping list. And until you know what you’re looking for, don’t get too hung up on them.

So what exactly are the four Cs?


We believe this is the most important aspect of any diamond. The cut of your diamond is the only element that is not determined by nature. You want your diamond to sparkle, and that relies on an excellent cut. If it’s too deep or too shallow the light won’t reflect as well as it could, making all other characteristics, such as clarity, completely obsolete.

So whilst we’d advise you to keep an open mind when it comes to some of the other Cs, the cut is one aspect of your purchase where there should be little or no compromise.


Ironically, the rarest and most valuable diamond colours (grades D, E and F) are actually deemed ‘colourless’. The further down the scale you go, a colour becomes more apparent. But at the top end, differentiating by colour is a little more tricky. So often a better question to ask is ‘which stone looks the brightest?’

The stone’s ‘brightness’ makes a difference to the finished piece and is a far more visible aspect than, say, clarity. So unless you’re looking for a specific colour, try to stay as close to colourless as you can.


It’s very easy to get hung up on the clarity of a diamond. However, sometimes clarity isn’t all that important. Without a doubt, a flawless stone will give you a better sparkle.

But perfection comes at a price – and a diamond doesn’t have to be perfect to be wonderful. Which is why we’ll always encourage you to examine a diamond through a jeweller’s loupe. You’ll be able to see where the naturally occurring inclusions are and make a decision based on the merits of the individual diamond, not just the statistics.

Of course, we don’t advocate that you settle for anything riddled with black marks throughout. But a good SI1… if you love it, it sparkles, and there are no inclusions visible to the naked eye, why not?


The size of a diamond (if it’s cut well), is decided by its carat weight. As most diamonds are much less than a carat in size, a single carat is also divided into 100 smaller units of measurement called points. The average customer may be buying a stone of, say, 50 points (0.50ct), which is half a carat.

By nature, quite a lot of ladies gravitate towards the larger diamonds we have in our counters. And certainly, they can be pretty impressive. But don’t forget, size isn’t everything! In fact, size alone doesn’t actually mean very much at all.

Diamond Certificate

A final consideration that’s often overlooked is the Diamond Certificate. All of the above points should be explained to you by the jeweller, and verified by an independent laboratory in a report – your diamond certificate.

As with any item of value, your insurer will prefer a certificate for your purchase from a trusted source. Well-respected labs include the GIA, HRD, and IGI. Be wary of any salesperson pushing an ‘in-house’ certificate, as often this has not been undertaken by a qualified diamond grader and is most probably worthless.


If you’re out diamond shopping this weekend, here are some tips to make your expedition a little easier.

  • If the price of a loose diamond seems too good to be true, it probably is. Particularly when you are considering buying a loose diamond online without being able to see it first. There’s a big playing field in each and every diamond attribute. Just because it’s a VS2 doesn’t mean there won’t be a visible surface inclusion. There are many ways to be caught out when buying diamonds, which is why we recommend a good jeweller – it’s our duty of care to talk you through each diamond before spending your hard earned cash!


  • If you’re shopping for a diamond together, talk budgets before you leave the house! Sometimes, not knowing the general budget can leave your future spouse uncomfortable in picking rings to try on – just in case they are over budget. We can work to any price range, so just set a rough bracket and we will take it from there.


  • Consider as many different shapes and styles as you can. Don’t be intimidated by pushy salespeople or feel you have to buy something on the spot. In our store, we will always have a loose diamond to fit with your hopes and dreams and any item of jewellery can be made up to order.


  • If you’re choosing a diamond as a surprise, keep it simple. Do your big thinking in advance. What’s his/her fashion style, build, and even job? Which ring is going to fit into their lifestyle? Again, we are on hand to help with this, and take you through the process.


Finally, keep looking until you find something you love. And enjoy the search!