April Birthstone Diamond: How to Choose the Right One
Updated: Sep 19
Diamond may be the world’s best-known gemstone, yet it remains one of the easiest to buy badly.
Two diamonds can appear similar on a laboratory report but look remarkably different in person. Equally, two stones with comparable sparkle may carry very different prices because of subtle differences in rarity, quality or origin.
If you are choosing an April birthstone diamond, the aim should not be to chase the highest grades. It should be to understand which qualities you can actually see, which claims can be verified and which features genuinely matter to you.
Why Is Diamond April’s Birthstone?
Diamond is recognised on modern birthstone lists as the gemstone for April. It is also traditionally associated with 60th and 75th wedding anniversaries.
Natural diamonds formed deep within the Earth, often more than a billion years ago. Their combination of geological age, brilliance and durability has made them powerful symbols of commitment, resilience and enduring love.
However, romance should never replace careful assessment—particularly when a small difference in quality can significantly affect the price.
Understanding the 4Cs of Diamond Quality
The 4Cs: cut, colour, clarity and carat weight—provide a shared language for describing diamond quality. They are useful, but they should not be treated as a shopping list.
A laboratory grade describes certain characteristics. It does not tell you whether the diamond is beautiful, reasonably priced or right for the person who will wear it.
Cut
Cut has an enormous influence on how a diamond handles light. A well-proportioned stone can appear bright, lively and full of contrast, while a poorly cut diamond may look dark or lifeless despite impressive colour and clarity grades.
Shape and cut are not the same thing. Shape describes the outline: round, oval, pear, cushion or emerald cut, for example. Cut quality concerns the proportions, symmetry, polish and resulting light performance.
Round brilliant diamonds may receive a formal cut grade. Fancy shapes require more individual assessment because their proportions, outlines and light patterns vary considerably.
Colour
The standard colour scale for colourless to light-yellow natural diamonds runs from D to Z. D represents the rarest colourless end of the scale.
That does not mean everybody needs a D-colour diamond. Several neighbouring grades may appear remarkably similar once the stone is mounted, particularly when viewed without a comparison stone beside it.
The setting also matters. Yellow or rose gold can complement a warmer diamond, while white metals may make subtle colour differences easier to notice.
Clarity
Most diamonds contain internal characteristics called inclusions and surface features called blemishes.
Higher clarity grades are rarer and usually more expensive, but the highest grade is not automatically the best use of your budget. An inclusion that cannot be seen without magnification may have little effect on the diamond’s appearance.
Its position and nature matter as much as its size. An inclusion beneath the table may be more noticeable than one near the edge, while certain inclusions may affect durability rather than simply appearance.
The practical question is not just, “What is the clarity grade?” It is, “Can I see the inclusion, and does it affect the beauty or security of this particular diamond?”
Carat Weight
Carat measures weight, not visible size.
Two diamonds of identical carat weight can look different in diameter because their proportions distribute the weight differently. A deep stone may conceal more of its weight below the setting, while another may appear larger from above.
Prices can also rise sharply around popular milestone weights. A beautifully proportioned diamond just below one of these thresholds may offer better visual value than a heavier stone chosen simply for the number on its report.
Natural or Laboratory-Grown Diamond?
Natural and laboratory-grown diamonds are both diamonds. They have essentially the same chemical, physical and optical properties, although they form in entirely different environments.
Natural diamonds developed within the Earth over immense periods of geological time. Laboratory-grown diamonds are manufactured using technology that recreates the conditions required for diamond growth.
They should not be confused with diamond simulants such as cubic zirconia, moissanite, white sapphire or zircon. These may resemble diamond, but they are different materials.
Laboratory-grown diamonds can allow buyers to choose a larger stone or higher apparent quality for the same budget. Natural diamonds appeal to buyers who value geological rarity, natural origin and the story of a gemstone formed within the Earth.
Neither choice is automatically more ethical, sustainable or financially sensible. Those claims require evidence. Laboratory production uses energy, while natural diamond supply chains vary greatly in their environmental and social practices.
If you would prefer a different white gemstone entirely, my separate guide to gemstones that look like diamonds compares the leading alternatives.
What a Diamond Laboratory Report Can, and Cannot, Tell You
For a significant diamond purchase, ask for a report from an appropriate, recognised independent gemmological laboratory.
The report should clearly identify whether the diamond is natural or laboratory-grown and record its measurements, carat weight and relevant quality characteristics. Any detected treatments should also be disclosed.
Verify the report number through the laboratory’s official website and check that the measurements match the stone. If the diamond has a laser inscription, confirm that it corresponds with the report.
A laboratory report does not establish:
whether the asking price is fair;
whether the diamond is attractive in person;
whether its proportions suit your preferences;
whether it has been responsibly sourced;
whether it will retain its purchase price; or
whether it is the right diamond for you.
My Gem Certification Guide explains how to verify and interpret gemstone laboratory reports.
Can a Diamond Be Guaranteed Ethical?
Terms such as “ethical”, “responsibly sourced” and “conflict-free” should never be accepted without asking what they actually mean.
The Kimberley Process regulates the international trade in rough diamonds under a specific definition of conflict diamonds. It does not provide a complete ethical history of every finished diamond.
Read more in The Kimberley Process Explained.
If provenance matters to you, ask the seller:
What evidence supports the stated source?
Can the supply chain be traced beyond a general assurance?
Is the country or mine of origin documented?
What responsible-sourcing standards does the seller follow?
Are recycled, antique or fully traceable options available?
For laboratory-grown diamonds, what is known about the manufacturer and energy source?
Absolute assurances should be treated cautiously unless they are supported by verifiable evidence.
Look Beyond the Laboratory Grades
Always examine a diamond with your eyes as well as its report.
View it in ordinary indoor lighting and natural daylight, not only beneath intense jewellery-shop spotlights. Compare several stones beside one another and look for brightness, fire, pattern and movement.
With elongated shapes such as ovals, pears and marquises, examine the bow-tie effect across the centre. A little contrast may give the stone character, but a dark and dominant bow tie can reduce its face-up appeal.
Fluorescence should also be judged individually. It is not automatically good or bad. The important question is whether it affects the diamond’s appearance under different lighting conditions.
Most importantly, do not pay for grades you cannot appreciate simply because they look impressive on paper.
My Diamond Buying Checklist
Before buying an April birthstone diamond, check:
Is the diamond natural or laboratory-grown?
Is there a report from a recognised independent laboratory?
Can the report number be verified online?
Do the measurements and any inscription match the diamond?
Have any treatments been disclosed?
Does the diamond look bright and attractive in different lighting?
Are any inclusions visible or potentially vulnerable?
Does its face-up size suit the carat weight?
What evidence supports any origin or ethical-sourcing claims?
Have the returns, resizing and aftercare terms been provided in writing?
Does the price make sense when compared with genuinely similar stones?
Would you still choose this diamond without the sales pressure or impressive terminology?
Choosing a Diamond for an Engagement Ring
An engagement ring must work for the person wearing it—not simply perform well on a grading report.
Consider lifestyle, personal taste, hand shape and how frequently the ring will be worn. Pointed shapes such as pear, marquise and princess cuts require settings that protect their more vulnerable corners.
Diamond is rated 10 on the Mohs scale and is exceptionally resistant to scratching. However, hardness does not make it indestructible. A sufficiently strong impact in the wrong direction can chip or cleave a diamond.
The security and quality of the setting therefore matter just as much as the stone. Have the claws or bezel checked periodically, particularly if the ring is worn every day.
If you want a ring created around the person rather than selected from a showroom tray, explore my custom gemstone jewellery service.
Frequently Asked Questions
Which of the 4Cs matters most?
There is no single correct answer, but cut often has the greatest visible influence on the beauty of a round brilliant diamond. The best choice usually balances all four factors rather than maximising one at the expense of the others.
Do I need a flawless diamond?
No. Many inclusions cannot be seen without magnification. Paying for an extremely high clarity grade may offer little visible benefit if a lower-graded diamond appears clean to the unaided eye.
Are laboratory-grown diamonds real diamonds?
Yes. Laboratory-grown diamonds possess essentially the same chemical, physical and optical properties as natural diamonds. They are not the same as simulants such as cubic zirconia or moissanite.
Does a laboratory report prove that a diamond is ethical?
No. A grading report describes the diamond and its quality characteristics. It does not automatically establish the complete provenance, environmental impact or working conditions behind it.
Can a diamond chip?
Yes. Diamond is highly resistant to scratching, but it can chip or cleave if struck forcefully in a vulnerable direction. A secure, appropriate setting helps protect it.
Choose the Diamond, Not Just the Grades
The right diamond is not necessarily the one with the highest colour, clarity or carat weight. It is the one whose beauty, documentation, provenance and price make sense together.
If you would like independent help defining your requirements, comparing options or finding a particular diamond, explore my Gemstone Sourcing Service. I work for the buyer, not the seller.
Information reviewed: September 2026.
Kim Rix GG GIA
Independent Gemstone Sourcing Specialist
Gemstone Detective
