Diamond 101 · A Bench Jeweler's Primer

Everything you wish someone had told you before looking into a jewelry case.

No gemology degree required. This is the same conversation we'd have across the counter — what each cut shape actually looks like on a hand, what the four Cs really mean (and which ones to spend on), how lab-grown and natural diamonds compare in 2026, and what every fancy color in the configurator is, where it comes from, and what it costs.

Cut shapes The four Cs Eye-catching score Clarity grades Lab vs natural Fancy colors

Eight cut shapes, plain English

Shape is the first decision — it sets the personality of the ring more than anything else. Here's what each one is, what the bench loves about it, and who it tends to suit.

Round Brilliant

The default. Maximum sparkle, maximum resale, maximum demand.

Fifty-eight precisely angled facets engineered to throw white light back at the eye. About 60% of every engagement ring sold is a round — and there's a reason. Done well, nothing else competes for raw fire.

Pros

+Most sparkle of any cut, by a wide margin.
+Easiest to grade — a tight Excellent/Excellent round is unambiguously brilliant.
+Holds resale value better than any fancy shape.

Cons

−Highest price per carat — you pay a premium for the cutting waste.
−Faces up smaller than elongated shapes of the same weight.

Tends to suit

The classicist. Anyone who wants the ring to read instantly across a room and never go out of style.

Oval

A round, stretched. Reads bigger on the hand for the same carat.

An elongated brilliant — same fire as a round, but the long axis tricks the eye into seeing more stone. Slender fingers love an oval. The trade-off is a faint dark band down the center called the bowtie; pick a stone where it's subtle.

Pros

+Faces up roughly 10% larger than a round of the same weight.
+Elongates the finger — flattering on most hands.
+Cheaper per carat than a round.

Cons

−Bowtie effect is real on poorly cut ovals — always inspect face-up.
−No standardized cut grade, so cut quality varies more than rounds.

Tends to suit

Anyone who wants visible size for the budget without sacrificing brilliance.

Princess

Square top, sharp corners, modern geometry.

Cut from a four-sided pyramid of rough, the princess is the most efficient brilliant cut — the cutter wastes less rough than a round, which is part of why it lists for ~30% less per carat. Sharp corners read clean and architectural; they also need protection in the setting.

Pros

+30–40% less per carat than a comparable round.
+Modern, clean, architectural look.
+Strong brilliance — second only to round in fire.

Cons

−Sharp corners chip more easily than rounded shapes — needs prongs that cover them.
−Inclusions near the corners are riskier than in a round.

Tends to suit

The contemporary buyer who wants a clean geometric look and serious savings versus round.

Cushion

A romantic compromise — square outline, rounded corners, candlelit fire.

Big, soft facets with rounded corners that catch warm light beautifully. Often called the 'pillow cut,' it pairs well with vintage settings and reads soft and feminine. Modern cushions throw broader flashes of light than a round; older 'old mine' cushions read more like a chandelier.

Pros

+Romantic, vintage-friendly silhouette.
+Larger facets show off color — beautiful in fancy yellows and pinks.
+Less expensive per carat than round.

Cons

−Broader flashes mean less constant sparkle than a round.
−Can hide tint in lower color grades — go a half-grade higher than you would for a round.

Tends to suit

Romantics. Anyone drawn to vintage settings or thinking about a fancy color stone.

Emerald

Step cuts. Long flashes of light. Architectural and grown-up.

Rectangular with cropped corners and parallel step facets that give a hall-of-mirrors effect instead of the brilliant-cut sparkle. Emerald cuts hide nothing — every inclusion and every off-color note shows. Reward: when the stone is clean, it's the most sophisticated shape in the case.

Pros

+Elongates the finger like an oval.
+Step facets give a calm, sophisticated, art-deco look.
+Faces up larger than its carat weight.

Cons

−Inclusions show — VS1 or better is the practical floor.
−Color shows too — stay G or better in white metals.
−Less raw sparkle; this isn't the cut if 'fire' is your priority.

Tends to suit

Buyers who want quiet sophistication over loud sparkle. Lovers of art-deco and minimal settings.

Pear

Half oval, half marquise — a teardrop with a point.

An elongated brilliant tapering to a point. Worn point-up, it elongates the finger more than any other shape. The pointed tip is delicate and needs a v-prong to protect it, and the bowtie problem from ovals shows up here too.

Pros

+Most elongating cut on the finger.
+Distinctive without being divisive.
+Faces up larger than rounds of the same weight.

Cons

−Pointed tip needs careful prong protection.
−Bowtie effect on poorly cut stones.
−Symmetry matters — uneven shoulders are visible from across a table.

Tends to suit

Buyers who want something distinctive but rooted in a classic shape.

Marquise

Long, pointed at both ends. Maximum face-up size for the carat.

Named for the Marquise de Pompadour, this cut has the largest crown surface area of any shape — a 1.0ct marquise looks like a 1.3ct round on the hand. The trade is two delicate points and a pronounced bowtie that requires careful selection.

Pros

+Largest face-up size per carat of any cut.
+Strong, vintage-inflected silhouette.
+Elongates the finger dramatically.

Cons

−Two pointed ends — both need protection.
−Bowtie is more pronounced than in ovals or pears.
−Polarizing — people either love or pass.

Tends to suit

Bold buyers who want size on the hand and don't mind a strong, statement silhouette.

Radiant

The emerald's brilliant-cut cousin — square or rectangular with facet fire.

A trimmed-corner rectangle (or square) with a brilliant-cut facet pattern instead of the emerald's step cuts. Translation: the architectural outline of an emerald with the sparkle of a round. Hides inclusions better than an emerald, hides tint better too.

Pros

+Sparkle of a brilliant cut, outline of an emerald.
+Hides inclusions and slight tint better than emerald or round.
+Trimmed corners are durable — no fragile points.

Cons

−Less established secondary market than rounds.
−Can vary widely in length-to-width ratio — pick deliberately.

Tends to suit

Buyers who love the emerald shape but won't compromise on sparkle.

The four Cs — in the order that matters

Every diamond is graded on four traits. They are not equal in importance, and they are definitely not equal in price impact. Here is the order of priority we'd use at a college budget — the same trade-offs the Stone Concierge applies under the hood.

Cut

Most important

Cut is the only C the cutter controls — and it's the one the eye actually reads. Two stones with identical carat, color, and clarity can look like night and day based on cut grade alone. Cut governs sparkle. Sparkle is what people see across a room.

Buy this way

Don't compromise. Excellent on a round, Very Good or better on a fancy shape. Skimp anywhere else first.

Color

Trust your eye

Graded D (truly colorless) through Z (light yellow). The lab certificate sees differences your eye won't — a G next to a D is invisible in a real setting under real light. The metal you pair with the stone matters more than chasing one letter higher.

Buy this way

White gold or platinum: G–H is the sweet spot. Yellow or rose gold: I–J reads white against the warm metal and saves real money.

Carat

Spend deliberately

Carat is weight, not size — and prices jump at round numbers (1.00, 1.50, 2.00). A well-cut 1.45ct often wears identically to a 1.50ct on the hand for noticeably less. Pair carat with cut: a 1.50ct Excellent looks bigger than a 1.70ct Good.

Buy this way

Pick the visual size you want, then shop just under the round-weight breakpoint. 0.95, 1.45, 1.90, 2.40 — those are sweet spots.

Clarity

Eye-clean is the bar

Inclusions are the natural marks inside every diamond. From VS2 up, the stone is 'eye-clean' — meaning no one is finding the inclusion at arm's length. FL and IF grades are jewelry-box trophies; they don't look any better on the finger.

Buy this way

VS1 or VS2 almost always. SI1 if a face-up inspection comes back clean — that's where the real money saves are.

The Eye-Catching Score — grade your own cert

Type the numbers from your GIA, IGI, or AGS report into the fields below. We compare each proportion — table %, depth %, crown and pavilion angle, girdle, culet, polish, and symmetry — against the well-cut zone for the chosen shape, then weight them into a single 0–100 score with a per-metric breakdown so you can see exactly which numbers are pulling the grade up or down.

From your cert

Open your GIA, IGI, or AGS report and type the values into the fields below. Numbers update the score live.

Shape

Measurements (mm)

Length

Width

Depth

Proportions

Table %

Depth %

Crown angle °

Pavilion angle °

Finish & feature grades

Cut grade

Girdle

Culet

Polish

Symmetry

100

of 100

Eye-Catching Score

Stellar

100

of 100

Eye-Catching Seal

Stellar

Awarded to stones whose proportions land in the well-cut zone for their shape.

Hall-of-fame proportions for a Round. This is what a textbook ideal looks like.

Per-metric breakdown

Cut grade

You: Excellent·Ideal: Excellent

Ideal100

Table

You: 56.0%·Ideal: 54% – 57%

Ideal100

Depth

You: 61.5%·Ideal: 60.5% – 62.5%

Ideal100

L / W ratio

You: 1.00:1·Ideal: 1.00:1 – 1.02:1

Ideal100

Crown angle

You: 34.5°·Ideal: 34.0° – 35.0°

Ideal100

Pavilion angle

You: 40.8°·Ideal: 40.6° – 41.0°

Ideal100

Girdle

You: Medium·Ideal: Medium / Slightly Thick

Ideal100

Culet

You: None·Ideal: None / Very Small

Ideal100

Polish

You: Excellent·Ideal: Excellent

Ideal100

Symmetry

You: Excellent·Ideal: Excellent

Ideal100

Computed in your browser — we never store the cert numbers you type. The Eye-Catching Score weighs each proportion against the published well-cut zone for the chosen shape; nothing is opinion.

Clarity grades — what FL, VVS, VS, SI, and I mean

Every diamond on a GIA, IGI, or AGS report carries a clarity grade. The scale is the same regardless of lab. Here's what each grade looks like in real life — and where to actually spend.

CleanestMost included

VVS1

VVS2

VS1

VS2

SI1

SI2

I1 – I3

Trophy Invisible to eye Sweet spot Inspect first Not for a center stone

Eye-clean

FL · Flawless

No inclusions or surface marks at 10× magnification. The top of the scale.

A trained grader using a 10× loupe finds nothing — no internal inclusions, no surface blemishes. Less than 1% of all diamonds make it here, and on the natural side it's vanishingly rare. Lab-grown FL stones exist but still command a serious premium.

Spend here when…

Trophy grade. Looks identical to VS1 face-up on a finger — you're paying for the certificate, not the appearance.

Eye-clean

IF · Internally Flawless

No internal inclusions; trivial surface blemishes only. Indistinguishable from FL on a finger.

Same internal cleanliness as FL — the only marks a grader can find are on the surface, and they're often things a polish would remove. Optically identical to FL in any real-world setting.

Spend here when…

Same trophy logic as FL. The premium over VVS makes sense for a collector, almost never for a wearer.

Eye-clean

VVS1 · Very, Very Slightly Included

Inclusions so tiny a grader needs minutes at 10× to locate them. Invisible to the eye.

Inclusions are minute pinpoints, usually only visible from the pavilion (the bottom) under magnification. Optically clean from every angle. The 1 vs 2 split is about how easy the inclusion is to find under 10× — neither is visible to your eye.

Spend here when…

Beautiful, expensive, optically equivalent to VS face-up. Worth it only if certificate prestige matters to you.

Eye-clean

VVS2 · Very, Very Slightly Included

Same as VVS1 to the eye — slightly easier for a grader to spot the inclusion at 10×.

Pinpoint or tiny feather inclusions visible from above under 10× magnification, but not without a loupe. Optically indistinguishable from VVS1 in a setting.

Spend here when…

Same advice as VVS1. If you're stretching to VVS, the small premium for VVS1 buys you nothing visible.

Eye-clean

VS1 · Very Slightly Included

Minor inclusions easy for a grader to find at 10×, invisible at arm's length. Sweet spot starts here.

Small crystals, feathers, or clouds that a grader catches in seconds at 10× magnification — and that no one else will ever see. VS1 is the threshold most jewelers quietly recommend if budget allows: certifiably clean and visually indistinguishable from anything above it.

Spend here when…

Default recommendation for emerald, asscher, and any other step cut where inclusions show more readily. Excellent value across all shapes.

Eye-clean

VS2 · Very Slightly Included

Slightly larger or better-positioned inclusions than VS1 — still eye-clean in any normal setting.

Inclusions easier to find at 10× than VS1, but still nothing visible without magnification. The single most popular grade we sell because the price-to-look ratio is excellent. Just confirm the inclusion isn't sitting dead-center under the table — a graded plot on the cert tells you instantly.

Spend here when…

The mainstream sweet spot. Where most well-advised buyers land for round, oval, princess, cushion, and radiant cuts.

Eye-clean

SI1 · Slightly Included

Inclusions easy to find at 10×, but most SI1 stones still face up eye-clean.

Inclusions are bigger or in less ideal positions — they take a grader no effort to locate. Most SI1 stones are still eye-clean at arm's length, but not all of them. This is where face-up inspection (or a trusted video) becomes mandatory before buying.

Spend here when…

Where the real savings live — often 25–40% less than VS2 for an indistinguishable face-up look. We hand-inspect every SI1 we sell.

Inspect

SI2 · Slightly Included

Inclusions sometimes visible to the unaided eye. Inspection is non-negotiable.

Inclusions are clearly visible at 10× and may be visible to a careful eye in good light. A genuinely eye-clean SI2 exists and represents huge savings, but it's the exception, not the rule. Never buy SI2 sight-unseen.

Spend here when…

Possible deal if (and only if) the stone is verified eye-clean in person or on high-resolution video. Not for buyers who can't inspect first.

Inspect

I1 – I3 · Included

Inclusions clearly visible to the unaided eye. Often affects sparkle and durability.

Inclusions are obvious without magnification, sometimes affecting how the diamond returns light or — at the I3 end — the structural integrity of the stone. Acceptable for accent stones in less critical positions; not recommended for an engagement-ring center stone.

Spend here when…

Skip for a center stone. Fine for melée, side stones, or fashion pieces where the look is the point and the cert isn't.

GIA, IGI, and AGS use the same eleven-grade scale. "Eye-clean" isn't a grade — it's a description we apply after a face-up inspection of the actual stone.

Lab-grown vs. natural

They are both real diamonds — same crystal lattice, same hardness, same optical properties, same grading scale. The difference is the origin story and what that does to the price tag.

Lab-grown

Grown in weeks, identical at the atom

Lab diamonds are produced two ways. HPHT (High Pressure, High Temperature) recreates the geological furnace deep in the mantle — a tiny seed crystal grows under thousands of atmospheres of pressure for a few weeks. CVD (Chemical Vapor Deposition) sets the seed in a chamber and flows a carbon-rich gas over it; the carbon precipitates onto the seed atom by atom. Both produce real diamond crystal — same hardness (10 on Mohs), same refractive index, same fire.

The price gap exists because supply is elastic. Indian and Chinese fabs scaled hard from 2022 onward; lab round wholesale prices have fallen ~30% year over year while supply keeps expanding. That means a real, eye-clean 1.50ct on her hand for what a 1.00ct natural would cost in a mall case.

40–70% less per carat than a natural of the same grade.
IGI is the dominant grading lab; AGS and GIA also grade lab now.
Resale is weaker — this is a "wear it forever" purchase, not an investment.
Most lab stones are laser-inscribed on the girdle with the cert number — easy to verify.

Natural

A billion years in the making

Natural diamonds formed 100+ kilometers below the surface, 1–3 billion years ago, then rode kimberlite eruptions toward the crust where they could be mined. The supply is finite, and that finiteness is what's priced in. A natural stone also carries provenance — origin tracing back to a specific mine is now standard for GIA-graded naturals over 1 carat.

Naturals hold resale value substantially better than lab stones — partly the scarcity, partly the cultural weight. If story and heirloom matter, a natural is the tradition. If maximum stone for the dollar matters, lab wins.

Roughly 2x the price per carat of a comparable lab stone.
GIA is the gold-standard grading lab for naturals.
Holds resale value — the secondary market exists and is liquid.
Treatments (HPHT color enhancement, fracture filling) are rare and always disclosed on the cert. Untreated is the default.

From the bench

There is no wrong answer. Both are real diamonds. Most BYU and UVU couples we work with end up with a lab-grown IGI stone — same crystal structure as natural, same grading scale, roughly half the price. If she has a strong preference for a natural GIA stone for the heirloom story, we source those too. Either way, the cert report — not the marketing — is the source of truth.

Fancy colors — the configurator palette

Six colors are available as alternates to a colorless center stone in every Featured Pairing. Each one comes from a different geological — or laboratory — story, and each carries a different price multiplier on top of the base diamond price.

×1.05

Champagne

Diamond price multiplier ×1.05

Origin

Warm brown-yellow tone, mostly mined in the Argyle and Ellendale fields in Western Australia. Lab versions exist but the natural color is more common — and more affordable than the colorless equivalent.

Rarity & price

Common in the natural market. The least expensive way into a fancy color — usually a quiet 5% premium over a colorless stone of the same weight.

Styling

Sings in rose and yellow gold. Pairs well with vintage and bezel settings where the warm tone reads intentional.

×1.30

Fancy Yellow

Diamond price multiplier ×1.30

Origin

Naturally caused by traces of nitrogen in the carbon lattice. Lab-grown yellows are typically HPHT-treated to deepen the saturation — disclosed on the cert, no different optically.

Rarity & price

Most accessible of the saturated fancy colors. Roughly a 30% premium over a comparable colorless stone — meaningful, but not breaking the bank.

Styling

Built for yellow gold. Reads almost canary in a halo of colorless pavé. Cushion and radiant cuts saturate the color most beautifully.

×2.20

Fancy Pink

Diamond price multiplier ×2.20

Origin

Natural pinks come almost exclusively from the now-closed Argyle mine in Australia — which is why prices have climbed steadily since 2020. Lab-grown pinks are typically irradiated post-growth to achieve the color, fully disclosed.

Rarity & price

Genuinely scarce in the natural market. Prices roughly double a colorless stone of the same grade — and rising. Lab-grown pinks are far more accessible.

Styling

Stunning in rose gold (which echoes the tone) or platinum (which lets the pink do all the work). Cushion and oval cuts hold pink saturation best.

×2.40

Fancy Blue

Diamond price multiplier ×2.40

Origin

Natural blues owe their color to trace boron in the crystal — the famous Hope Diamond is one. Lab-grown blues are produced via boron-doping during HPHT growth, which mimics the same atomic mechanism.

Rarity & price

The rarest mainstream fancy color in the natural market. Carries the highest premium in our palette — roughly 2.4x the colorless price.

Styling

Platinum or white gold lets the blue speak. Bezels and modern solitaires; avoid yellow gold, which fights the cool tone.

×1.85

Fancy Green

Diamond price multiplier ×1.85

Origin

Natural greens get their color from millennia of natural radiation exposure deep underground. Lab-grown greens are typically produced via post-growth irradiation that replicates the same effect — disclosed on the cert.

Rarity & price

Rare and unusual. Roughly 1.85x the colorless price. Most green stones show color only on the surface skin, which is why a true 'fancy green' through-and-through is genuinely uncommon.

Styling

Quiet, surprising, never loud. Pairs well with yellow gold (echo) or platinum (contrast). A favorite for grooms who want something no one else in the family will be wearing.

×1.40

Fancy Black

Diamond price multiplier ×1.40

Origin

Natural blacks (carbonado) are dense with graphite and microscopic inclusions — the inclusions are what make the stone opaque. Lab-grown blacks are typically irradiation-treated to achieve full opacity.

Rarity & price

Common as a category, but high-quality blacks with a polished, mirror-like surface are harder to find. Roughly a 40% premium over the colorless equivalent.

Styling

Modern, edgy, gender-fluid. Looks striking in white metals, dramatic in yellow gold. Increasingly popular as a center stone in men's bands and alternative engagement rings.

Multipliers shown are applied to the diamond price only — the setting and metal are unchanged. Numbers mirror the configurator's source of truth so what you read here is exactly what you'll see when you build.

Read enough? The Atelier Collection is what's actually on the bench right now — semi-mounts and finished rings hand-set by our atelier partner, ready to ship.

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