Diamonds might be the most precious of all gemstones, but not all diamonds are created equal. Thanks to a combination of colour, cut, clarity and carat weight, diamonds vary wildly in price and quality.

One of these ‘four Cs’ is clarity, indicating the presence (or absence) of inclusions within the diamond.

The ‘I’ in the I1 clarity grade stands for ‘included’, because I1-graded diamonds have inclusions, or clarity characteristics, that are visible to the naked eye, without any magnification.

The Included (I) category of grading includes three sub-categories: I1, I2, and I3. I1 is the highest grade within the Included category, with the least number of visible inclusions compared to I2 and I3 diamonds.

In diamond grading, inclusions refer to impurities or imperfections within the stone, such as black or white minerals, bubbles, internal cracks or feathering. Clarity grading also takes into account blemishes, which are found on the outside of a stone, including scratches or small pits. These inclusions are a result of the natural diamond formation process, which occurs deep within the Earth under intense heat and pressure.

When you look at an I1 diamond with the naked eye - that is to say, with no magnification - you will be able to easily spot inclusions within the stone.

These inclusions may be light or dark, and can appear as clouds, feathers, or crystals within the diamond.

The size, number, and location of these imperfections will vary from diamond to diamond. The one lovely thing about inclusions is that they make every diamond unique! However, inclusions are generally considered an undesirable characteristic. Inclusions in lab grown diamonds are referenced differently compared to natural diamonds, but they share similar characteristics and can also impact the diamond's appearance.

The quality, and value, of a diamond is determined by what we call the 4Cs: carat weight, colour, clarity, and cut. It is the combination of all these factors that influence a diamond’s beauty and value.

In theory, an I1 diamond with a good cut and a colour grade may be a better quality diamond than an SI diamond (a higher clarity grade) with a poor cut or lower colour grade. It all depends on how the specific diamond behaves and looks. Where and what type the inclusions influences how much they impact the overall look of a diamond. Natural diamonds, formed deep within the Earth, have unique inclusions that differ from those found in lab-grown diamonds, which use different grading terminologies for similar inclusions.

With that said, the inclusions of an I1 diamond are always be visible enough to be seen by the naked eye. For most people, this will be disappointing and perhaps spoil the enjoyment of the diamond. It is for this reason we don’t offer I1 diamonds here at Harper Tait. Our minimum quality is an eye-clean SI2.

Read more about diamond clarity .

Diamonds sparkle due to their ability to reflect light. Although it will vary from stone to stone, a high number or size or inclusions may impact a diamond's ability to reflect light, and therefore affect how much it sparkles.

So diamonds with visible inclusions may have less sparkle compared to diamonds with higher clarity grades. However, the difference in sparkle may not be noticeable to the naked eye. One of the greatest impacts on a diamond's sparkle is the cut of the diamond. The faceted cut creates that bouncing of light within a diamond - the refraction - that gives the stone its distinctive fire. It's possible a well-cut I1 diamond may still have a good amount of sparkle, despite its lower clarity grade.

It is impossible to know how a specific diamond's inclusions will affect its appearance and sparkle without examining the stone in person. For this reason, buying an Included diamond online or without viewing it is a particular risk. This is another reason we don't offer I1 or lower diamonds - the risk of disappointment is too high.

When it comes to your engagement ring, it’s important to choose a diamond that is not only visually appealing, but also durable enough to withstand everyday wear. Diamond engagement rings are a symbol of eternal commitment and love, making it crucial to choose a diamond that is both visually appealing and durable.

Diamond is one of the hardest materials on earth, but inclusions cause weak spots and may undermine the stone’s structure. It may be possible for a skilled setter to carefully set an included diamond to disguise the worst of a stone’s imperfections - such as positioning a dark inclusion or blemish under a claw - but an included stone is naturally more at risk of chipping or cracking.

Your engagement ring is a piece to treasure for life, so choosing a slightly higher clarity of diamond will give you the confidence it will stand the test of time.

Read more: What is the average price of an engagement ring? 

At Harper Tait, we pride ourselves on offering only the highest quality and most beautiful diamonds. That is why we do not offer I1 diamonds in our collection. While it's possible an individual I1 diamond might be an attractive and cost-effective stone, overall this grade has too many inclusions and blemishes to be confidently chosen for an engagement ring.

But rest assured - we understand budgets. When it comes to weddings, we know there's a lot to spend on. So whether you choose a ring from our signature collection, work with us on an heirloom rework, or go bespoke , we can help create the ring of your dreams without stretching your budget. We'll never suggest you spend more than you want to, and will help find solutions to get the look you love at a comfortable cost.

Or find your perfect diamond wedding ring or diamond engagement ring in our collection