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Do Lab-Grown Diamonds Get Cloudy Over Time? The Truth

No. A lab-grown diamond does not become cloudy, hazy or milky as it ages. It is crystallised carbon — chemically, physically and optically identical to a mined diamond — and it sits at 10 on the Mohs scale, the hardest known material on earth. It is chemically inert and non-porous, so there is no mechanism by which the crystal itself can degrade, dull or fog over the years.

When a diamond ring looks cloudy, one of two things is true: a film of oil and soap has built up on the outside of the stone, or the stone was cut from rough with clarity characteristics that made it look hazy from the very first day. The first is solved in twenty minutes at your kitchen sink. The second is solved at the point of purchase — by buying to a proper clarity standard in the first place.

Key takeaways

• Lab-grown diamonds do not degrade, cloud or lose brilliance with age. The material cannot change.
• The overwhelming cause of a "cloudy" diamond is a surface film of skin oil, hand cream, sunscreen and soap. Diamonds are oleophilic — they attract grease.
• A genuinely hazy stone was hazy on day one, usually from dense cloud inclusions or heavy graining in a low-clarity diamond. This affects mined and lab-grown diamonds equally.
• Clarity is the variable that decides this — not origin. At VVS1–VVS2, cloud inclusions are microscopic and a milky appearance is effectively off the table.
• Montare's house floor is D–E colour, VVS1–VVS2 clarity, Triple Excellent cut, IGI certified. That standard exists precisely so this question never becomes your problem.

Why a diamond physically cannot cloud over

It helps to be precise about what a diamond is. It is a single crystal of carbon atoms locked in a rigid tetrahedral lattice. That structure is what gives diamond its hardness, its refractive index, and its chemical inertness. It does not oxidise in air, it does not absorb water, it has no pores for anything to seep into, and at ordinary temperatures nothing in daily life is hard enough to abrade its surface.

A lab-grown diamond has exactly this same structure. It is grown rather than mined, but the end material is diamond in every measurable sense — the same hardness, the same dispersion, the same optical behaviour. Both mined and lab-grown diamonds rate 10 on the Mohs scale. This is the crucial point, and it is why the premise of the question quietly dissolves: whatever is true about a mined diamond's longevity is true about a lab-grown one.

Compare that with a simulant. Cubic zirconia is softer, more porous at the surface, and genuinely does abrade and cloud with a few years of daily wear. Much of the "lab diamonds go cloudy" folklore online is, we suspect, memory of cubic zirconia being transplanted onto a completely different material. If you want the distinction drawn properly, we cover it in lab-grown diamonds vs cubic zirconia and in lab-grown diamonds vs moissanite.

So why does my diamond look cloudy?

1. A film of oil on the surface — the cause in most cases

Diamonds are oleophilic: they are naturally attracted to oils and greasy substances. Every time you apply hand cream, cook dinner, put on sunscreen or simply touch the stone, you transfer a microscopically thin layer of oil onto it. That film settles particularly on the pavilion facets underneath the stone, which are the facets responsible for reflecting light back up to your eye.

Once those facets are coated, light no longer enters and exits cleanly. The stone stops returning light and starts looking flat and grey — exactly the symptom people describe as "cloudy". This is also why a ring can look spectacular in a showroom and disappointing three weeks later: nothing happened to the diamond, a film simply accumulated on it.

The fix is unglamorous and completely reliable. Soak the ring in warm water with a few drops of plain dish soap, leave it for twenty to forty minutes, brush gently around and underneath the stone with a soft toothbrush, rinse, and dry with a lint-free cloth. Our full method is in how to clean and care for your diamond ring.

2. Clarity characteristics that were always there

The second explanation is less comfortable but more important, because it is the one that cannot be fixed after the fact.

Some diamonds — mined and lab-grown alike — contain clouds: dense concentrations of minute pinpoint inclusions. When a cloud is large enough and positioned under the table, it scatters light passing through the stone and gives it a soft, milky, slightly out-of-focus look. Gemmologists sometimes describe these stones as "milky" or "hazy". Crucially, this is not something that develops. It is a property of the crystal that was present the day it was cut, and it will look exactly the same in fifty years.

Cloud-driven haze is overwhelmingly a phenomenon of the lower clarity grades — SI and I, occasionally VS. This is precisely the trade-off buyers make when they chase carat weight at the expense of clarity. Our explainer on diamond clarity, from VVS to SI sets out where the real thresholds are.

3. Strain and graining in some CVD stones

There is one factor specific to lab-grown diamonds worth being straight about. Most gem-quality lab-grown diamonds today are grown by chemical vapour deposition (CVD), in which carbon is deposited onto a seed layer by layer. Stops and starts in that vertical growth can leave behind planar clouds or internal graining — reflective lines or a faint oily, wavy texture visible through the table under magnification, as documented by GIA's Gems & Gemology research on CVD-grown diamonds.

In poorly controlled growth, heavy graining can contribute to a hazy look. In well-controlled growth it is negligible or absent. The honest framing is that this is a manufacturing-quality question, not a lab-grown-diamond question — and it shows up in the clarity grade, which is exactly what the grade is for. Notably, GIA's own survey work found that CVD samples clustered around VVS2–VS1, with a median clarity slightly higher than comparable natural diamonds, because the controlled growth environment produces fewer inclusions. If you would like the growth methods explained properly, see how lab-grown diamonds are made: CVD vs HPHT.

Film or the stone itself? How to tell

Question	Surface film	Inherent to the stone
When did it start?	Gradually, over days or weeks of wear	It looked this way from the beginning
Does cleaning fix it?	Yes — sparkle returns immediately	No — it looks identical after cleaning
Does it come back?	Yes, until you clean it again	It never changes either way
What does the certificate say?	Nothing — this is not a stone property	Often clouds or graining listed as the grade-setting characteristic
Typical clarity grade	Any grade — film does not discriminate	Usually SI or I; occasionally VS
Can it be corrected later?	Yes, in twenty minutes	No — the decision was made at purchase

The diagnostic is therefore simple. Clean the ring properly. If the brilliance comes back, you had a film and you always did. If it looks the same afterwards, you are looking at the stone itself — and the answer lay in how it was selected, not in how it has aged.

How to buy a diamond that will never look milky

Everything above collapses into a short buying rule: haziness is a clarity-selection outcome, so control clarity and the problem disappears permanently.

• Buy at VVS or better. At VVS1–VVS2 the inclusions present are microscopic and difficult to find even under 10× magnification. There is no cloud dense enough to scatter light across the stone.
• Read the certificate, not just the grade. Look at the comments and the plotted characteristics. If "clouds" or "graining" is named as the grade-setting characteristic on a lower-clarity stone, that is the flag. See how to read a diamond certificate.
• Insist on a reputable laboratory. Grading rigour varies. We use IGI for every stone, and explain why in IGI vs GIA for lab-grown diamonds.
• Do not trade clarity for carat. The most common route to a hazy stone is buying the largest carat weight a budget allows and letting clarity fall to SI to fund it.
• Prioritise cut. Cut governs how much light the stone returns in the first place. A shallow or steep stone looks lifeless even at flawless clarity — see what an ideal cut diamond is.

Why Montare

We built our house standard so that this question is answered before a client ever has to ask it. Every Montare diamond is lab-grown, D–E in colour, VVS1–VVS2 in clarity, Triple Excellent in cut, with ideal table and depth percentages for its shape, IGI certified, and never below 3 carats. We do not offer SI stones, so the clarity trade-off that produces milky diamonds is not one you can accidentally make with us.

That standard is also the honest case for lab-grown. Because the growth process is controlled rather than geological, this grade of material is attainable at a fraction of the mined equivalent — which is why our clients wear 3 carats of D–E VVS rather than one carat of something compromised. We set out the full comparison in lab-grown vs mined diamonds: the honest comparison, and the complete specification lives on our standards.

Every ring is made to order in Toronto, designed with you rather than picked off a tray, and backed by our lifetime promise. Browse the engagement ring collection to see how the standard reads in practice.

Keeping your ring bright

Because the only real enemy is film, care is genuinely straightforward. Clean the ring every two to four weeks with warm water and dish soap, paying attention to the underside of the stone where residue collects. Remove it before applying hand cream or sunscreen, before cooking, and before swimming in chlorinated water — chlorine will not touch the diamond, but it can attack the alloys in gold over time. Have the setting and prongs inspected once a year; a loose prong is a far more consequential problem than a dull stone, and far easier to fix early.

Frequently asked questions

Do lab-grown diamonds get cloudy over time?

No. Lab-grown diamonds are crystallised carbon at 10 on the Mohs scale — chemically inert, non-porous and unable to degrade under normal wear. A cloudy appearance is either a removable oil film or a clarity characteristic that was present from the day the stone was cut.

Why does my diamond look dull after a few weeks?

Almost certainly a film of skin oil, hand cream or soap on the pavilion facets beneath the stone, which blocks light from returning to your eye. A twenty-minute soak in warm soapy water and a gentle brush restores it completely.

Can a lab-grown diamond turn yellow?

No. Colour is a fixed property of the crystal and does not shift with age or wear. What can change is the metal around it — white gold is rhodium-plated, and as that plating wears the setting can warm in tone, which people sometimes read as the diamond yellowing. Replating restores it.

Are some lab-grown diamonds hazy from the start?

Yes, and so are some mined diamonds. Dense cloud inclusions or heavy graining can give a stone a milky look, most often at SI and I clarity. It is a selection issue rather than an origin issue, and buying at VVS removes it entirely.

Does CVD or HPHT growth make a difference to clarity?

Both methods produce gem-quality diamonds. CVD growth can introduce planar clouds or graining if poorly controlled, but any such characteristic is captured in the clarity grade — which is why the grade, and the laboratory that issued it, matter more than the growth method.

Will polishing or re-cutting fix a milky diamond?

Rarely, and it is seldom worth it. Clouds and graining are internal, so re-polishing the surface does not remove them, and re-cutting sacrifices carat weight for an uncertain result. The decision that matters is made before you buy.