How to spot a good diamond

How to spot a good diamond

Written by Alice Rochester on 9 November 2015

Here at HK Bespoke we often get asked what someone should be looking for when they’re looking at white diamonds.  There are four main points that people will tend to refer to when they reply to this question:

Colour –

There are several scales which have been introduced to help quantify how white a diamond is, but over the years the one that people keep coming back to is one that goes from D (the brightest and whitest) through to Z (a grubby-looking yellow / brown).  To be able to actually gauge how white a diamond is, the stone needs to be un-set, laid face down to prevent being distracted by sparkle, and compared to a set of master stones... not something that everyone has available to them! Anything I or above is considered white but we tend to suggest starting off at an H colour as most people can tell the difference in colour between an I and an H where they might not be able to tell the difference between an H and a G.  The further up the scale you go, the smaller the colour differences are and therefore the harder to tell apart.  Setting a stone that is less white into yellow gold or the natural creamy colour of 9ct white gold will make it appear whiter than it really is.  A nice trick if you have inherited a diamond which is not as white as you might like it to be otherwise!

Clarity –

This refers to any marks, known as inclusions, which you may see in the diamond.  If there are visible marks in the stone they can be a bit of a distraction and can even prevent light travelling through it, reducing sparkle.  This scale ranges from I (Included) where you can easily see any marks with the naked eye, through to Fl (Flawless) where there are no marks in the stone at all. Stones are usually examined with 10:1 magnification to gauge how clear they are and we would tend to recommend starting at Si, where there are Slight Inclusions in the stone, but they are only generally visible under magnification, so they’re unlikely to bother the wearer.  A more sparkly cut pattern like a brilliant or a princess cut will also help disguise any inclusions, where a step cut like a baguette or an emerald cut are more transparent, meaning there’s nowhere for the inclusions to hide, so you might like to start at a clearer, VS, instead – Very Slight Inclusions.

Cut –

The cut of a gemstone is how we refer to the shape and facet pattern of the diamond.  A modern, round stone with lots of sparkle is usually a brilliant cut, and if it has been cut properly, will reflect all the light that comes in through the top of the stone straight around and back out the top again without losing any out of the sides.  This is known as an ideal cut.  A square version of this stone is known as a princess cut.  If the diamond is cut too deep or too shallow the light doesn’t reflect in the same way and sparkle is reduced.  Step cuts are the other end of the spectrum of cut patterns – they tend to be square or rectangular in shape and have far fewer facets, so if you look in the top of the stone you feel like there are a flight of steps leading down into it.  They can be very hypnotic, and give a lower-key look because they draw light into them rather than throw it back out as more highly facetted stones do.  If you like the Art Deco style then step cuts are often the way to go.  Ovals, hearts and other shapes are referred to collectively as Fancy cuts and are often cut to maximise sparkle in the individual stone.

Carat –

Carat is a measure of weight in a diamond and as such can be the most difficult thing to see - who knows what one gram of anything looks like, let alone a unit of measurement that is unfamiliar in a material that we don’t often get to play with?!  In an ideally cut, round brilliant cut diamond there is a direct correlation between its diameter and its depth and therefore its weight, so you can say, for example, that a 5mm ideally cut diamond is likely to weigh around 0.5ct.  If the stone has been cut deeper, or more shallow than the ‘ideal’ measurements, though, it could weigh more or less than this, and in any other cut pattern this correlation can be a little looser anyway.  When we are talking to people about their diamonds in a consultation, we will often refer to the millimetre size since this means more to people than carat weight does.  That said, it is important to know the carat weight of a diamond since the value is defined as its price per carat.

But, the most important thing to look out for is...

that you like the stone.  It sounds obvious, but all the measurements in the world will never really define an individual’s sense of beauty.  You can’t say a building is beautiful because it’s 10m tall and has 5 windows and a door, so why should you be able to do this with diamonds?!  What you really need to do is look at a small selection of stones and see which one ‘speaks’ to you.  It’s not always the one that on paper is ‘the best’ as you might prefer the longer shape of that particular emerald cut or the roundness of that pear, which are things that you just don’t know until you see them in real life.  We work closely with our customers to talk to them about all these things in the consultation, getting to know people so well that even if they can’t come in to see the diamonds for themselves because of distance or time constraints we can help them chose the perfect diamond remotely.  Even if you don’t have the opportunity to come in to one of our studios to handle the diamonds for yourself you know that you will end up with the perfect diamond for your sense of style and budget.  Please feel free to contact us to talk about your hopes and dreams for your perfect diamond as we will be more than happy to help you find it.