Square vs Elongated Old Mine Cushion Cut Diamond: Which Is Best For Your Ring?

Square cushion vs elongated cushion cut diamond engagement rings on hand comparison
TL;DR

The biggest difference between a square old mine cushion and an elongated old mine cushion is proportion. A square old mine cushion typically has a length-to-width ratio of 1.00–1.10, creating the balanced, pillow-shaped silhouette most associated with antique diamonds. An elongated old mine cushion generally ranges from 1.15–1.40+, giving it a longer outline and greater finger coverage.

Both share the same antique faceting, high crown, small table, and open culet. The choice ultimately comes down to whether you prefer a classic square silhouette or a more elongated profile.

At Ouros Jewels, both silhouettes are available as IGI-certified lab-grown diamonds, which means you can get the rare elongated look, the one that's nearly impossible to source in genuine antiques, without the antique price tag or the long hunt.

What Is an Old Mine Cut Diamond?

An old mine cut is an antique diamond shape that was hand-cut, by eye, from roughly the early 1700s through the late 1800s, before mechanical bruting machines standardized diamond shapes. It is defined by:

  • 58 facets (the same count as a modern round brilliant, but arranged differently)
  • Taller profile
  • A smaller top surface (typically ~38–45% of the diameter)
  • A large, large culet, the bottom point is ground flat, creating a small "window" or circle visible when you look straight down through the table
  • A soft, squarish cushion outline with rounded corners

Because it was engineered for the warm, point-source light of candles and gas lamps, the old mine cut prioritizes fire (flashes of colored light) over brilliance (white sparkle). This is why collectors affectionately call them "candlelight diamonds."

What Is a Square Old Mine Cushion Cut Diamond?

A Square Old Mine Cushion Cut Diamond is the most traditional version of the antique Old Mine Cut. Defined by its soft square outline, rounded corners, high crown, small table, and open culet, it closely resembles the hand-cut diamonds that were popular from the 18th and 19th centuries. Unlike modern cushion cuts that prioritize intense brilliance, a square old mine cushion was designed to perform in candlelight, producing broad flashes of fire and a warm, romantic glow.

The square shape typically features a length-to-width ratio between 1.00 and 1.10, giving it a balanced and symmetrical appearance. This proportion creates the classic "pillow" silhouette that collectors and vintage jewelry enthusiasts associate with authentic antique diamonds.

One of the most unique characteristics of a square old mine cushion is its chunky faceting. Rather than the fast, splinter-like sparkle seen in many modern diamonds, it displays larger flashes of light that appear slower, deeper, and more dimensional. These broad reflections give the diamond a unique personality that many buyers describe as soft, romantic, and full of character.

What Is an Elongated Old Mine Cushion Cut Diamond?

An Elongated Old Mine Cushion Cut Diamond is an antique-style cushion diamond with a rectangular or elongated outline. It features the same high crown, small table, open culet, and chunky faceting found in traditional old mine cuts, but with a longer length-to-width ratio that creates a larger-looking, finger-lengthening appearance. 

Typically featuring a length-to-width ratio of 1.15 to 1.40 or greater, an elongated old mine cushion offers a softer, more elegant profile while preserving the warm, candlelit sparkle that makes antique diamonds so desirable. The extended outline also gives the stone greater visual spread, often making it appear larger than a square old mine cushion of the same carat weight.

One of the most appealing characteristics of an elongated old mine cushion is the way it balances vintage charm with modern wearability. Its broad flashes of fire and rare faceting deliver the romantic character of an antique diamond, while the elongated shape aligns with today's growing preference for longer diamond silhouettes.

The Core Difference: Shape, Not Architecture

Square cushion vs elongated cushion cut lab diamond shape comparison white background

Both stones are old mine cuts. Both have the deeper appearance, smaller top surface, open bottom, and broad chunky facets. What changes is the outline when you look down at the stone:

Feature Old Mine Square Cushion Old Mine Elongated Cushion
Length-to-width ratio ~1.00–1.10 ~1.15–1.40+
Silhouette Soft, balanced "pillow" square Longer cushion / oval-leaning
Look on the hand Centered, architectural, classic antique Finger-lengthening, graceful, modern-romantic
Perceived size Looks true to carat Often looks larger due to longer spread
Sparkle pattern Chunky flashes radiating from center Same flashes spread along a longer axis (more "theatrical")
Availability (antique) Easier to find Genuinely rare, difficult to find
Availability (lab-grown) Readily available Readily available & cut to exact ratio
Best for Longer fingers, vintage purists, heirloom feel Shorter/wider fingers, those wanting presence & a contemporary edge

Key takeaway: Choose square for a true-to-period, architectural antique look. Choose elongated for a longer line on the finger, more visual presence per carat, and a softer, more modern silhouette.

How Each One Looks on the Hand as a Ring

This is where most buyers actually decide.

  • Square old mine cushion sits centered on the finger and fills the width of the band. It draws the eye to the pillow outline and the chunky internal flashes. It tends to flatter longer, slimmer fingers, where its architectural balance shines.

  • Elongated old mine cushion runs along the finger, creating a longer, slimming line. It tends to flatter shorter fingers, wider fingers, or smaller hands, and it makes a given carat weight read larger because the surface area is stretched along one axis.

A practical example: a 2 ct square old mine cushion is a soft square presence, while a 2 ct elongated old mine cushion at a 1.30 ratio appears noticeably longer and more graceful, even though both weigh the same.

Approximate face-up spread by carat 

Carat Square (~1.05 L:W) Elongated (~1.30 L:W)
1.0 ct ~5.5 × 5.3 mm ~6.2 × 4.8 mm
1.5 ct ~6.3 × 6.0 mm ~7.1 × 5.5 mm
2.0 ct ~7.0 × 6.7 mm ~8.0 × 6.2 mm
3.0 ct ~8.0 × 7.7 mm ~9.2 × 7.1 mm

Dimensions are approximate and vary with cut depth and individual proportions. Always confirm the exact millimeter spread on the certificate.

Antique Natural vs. Lab-Grown Old Mine Cushion Diamonds

This is the decision competitors gloss over, and where Ouros Jewels IGI-certified lab-grown stones offer a clear advantage.

Factor Genuine Antique Old Mine (Natural) Lab-Grown Old Mine
Elongated availability Extremely rare, especially 2 ct+ Readily available, cut to your exact ratio
Color & clarity Often warmer (J–N), variable clarity Choose your grade; cleaner, higher-color options easy
Condition May have thin girdles, chips, wear Pristine, modern durability
Certification Often none / vintage appraisal only IGI certified with full specs
Price per carat Premium; elongated commands the most Significantly lower for the same look
Ethics & sustainability Mined origin (recycled/estate) Lab-grown, ethically sourced, sustainable
Customization Fixed, you take what exists Specify L:W ratio, carat, color, clarity, metal

Who should buy an antique old mine cushion? Buyers who value historical provenance, original period craftsmanship, and the uniqueness that comes with a genuine antique diamond. Keep in mind that antique stones can require more patience to source and may show signs of age or wear.

Who should buy a lab-grown old mine cushion? Buyers who love the antique look but want greater flexibility in size, color, clarity, and proportions. Lab grown old mine cushion diamonds also make it easier to find specific shapes, particularly elongated ratios while offering modern certification and consistent quality.

Common Myths About Old Mine Cushion Cuts Corrected

Myth 1: Old Mine Cuts Don't Sparkle

Old mine cuts do sparkle, but differently from modern brilliant cuts. Their larger facets produce broader flashes of light and stronger fire, creating a softer, more antique-style appearance rather than rapid scintillation.

Myth 2: Elongated Old Mine Cushions Are the Same as Modern Elongated Cushions

While both share a similar outline, their faceting is very different. An elongated old mine cushion features a high crown, smaller center area, and large culet, whereas modern elongated cushions are cut with contemporary proportions designed to maximize brilliance.

Myth 3: Lab-Grown Old Mine Cuts Aren't Real Old Mine Cuts

A lab-grown old mine cushion is still a real diamond. The difference lies in its origin, not its faceting style. Modern cutters can recreate the visual characteristics of antique old mine cuts while offering greater consistency and customization.

Myth 4: The Open Culet Is a Flaw

The open culet is one of the defining features of an old mine cut. What may appear unusual to buyers accustomed to modern diamonds is actually an intentional characteristic commonly found in antique diamond cutting.

Myth 5: Square Old Mine Cushions Are More Valuable Than Elongated Ones

Value depends on multiple factors, including carat weight, color, clarity, cut quality, and rarity. While elongated antique examples can be harder to find, neither shape is inherently superior.

Myth 6: Old Mine Cushions Look Smaller Than Their Carat Weight

Not necessarily. Face-up size varies by proportions, depth, and shape. Well-cut elongated old mine cushions, in particular, can appear larger due to their extended outline.

Myth 7: Old Mine Cuts Require High Color Grades

Many old mine cuts display warmth beautifully, especially when paired with yellow or rose gold. As a result, some buyers are comfortable selecting slightly warmer color grades than they might choose in a modern brilliant cut.

Choosing the Right Ring Setting for Each Cushion Shape

Both shapes love antique-friendly settings; a few pairings shine:

  • Bezel & half-bezel beautifully frames the cushion outline and protects the high crown; half-bezels especially flatter elongated stones.
  • East-west settings a modern, eye-catching way to show off an elongated old mine across the finger. 
  • Solitaire lets the chunky candlelight flash speak for itself; ideal for purists. 
  • Three-stone frames either shape with antique romance.
  • Halo small rose-cut or round accents reinforce the candlelit character and add presence.
  • Claw / compass prongs leave more of the crown visible so the chunky flash isn't interrupted.

Metal guidance: Yellow gold is the classic pairing it flatters warm antique tones. Rose gold adds warmth without pulling the diamond yellow. White gold/platinum works best with higher-color lab-grown stones where the body color stays crisp.

Which Old Mine Cushion Shape Is Right for Your Ring?

1

Look at Your Hand

Shorter or wider fingers generally suit elongated old mine cushions, while long, slim fingers pair beautifully with square cushions. Browse our collection to compare both silhouettes and find the shape that feels right for you.

2

Decide the Overall Style

Choose square if you love true antique proportions. Choose elongated if you want a more romantic look with additional finger coverage.

3

Choose Your Sparkle Pattern

Classic faceting delivers chunky antique flashes. Crushed-ice faceting creates a brighter, more modern shimmer.

4

Set a Realistic Budget

Lab-grown elongated old mine cushions offer the look at a lower cost, while genuine antiques often command a significant premium.

5

Verify the Details

Review the length-to-width ratio, millimeter measurements, and certification before purchasing.

6

View It in Natural Light

Request videos, real-life photos, or purchase from a retailer offering clear media and a customer-friendly return policy.

Bottom line: They're siblings, not rivals. Square preserves the original antique footprint; elongated stretches it for a longer, more contemporary silhouette. Both deliver the same warm, candlelit soul.

Types of Old Mine Cushion Cut Diamonds Available at Ouros Jewels

Ovalish Old Mine Cushion Diamonds

Designed with a softly elongated outline, providing additional finger coverage while maintaining old mine cut characteristics.

Old Mine Cushion with Rounded Corners

Featuring softer, more pronounced corners, this variation emphasizes the classic pillow-shaped appearance.

Old Mine Cushion with Criss Cut

Incorporates elongated step-like facets that create a hall-of-mirrors effect rather than traditional chunky flashes.

Fancy Colored Old Mine Cushion Diamonds

Available in shades such as yellow, pink, blue, champagne, and black, combining antique faceting with rare color.

Old Mine Cushions with Chunky Facets

Known for broad flashes of light and pronounced facet patterns that closely resemble historic hand-cut diamonds.

Old Mine Cushions with a Crushed Ice Look

Featuring a denser facet arrangement that produces a brighter and more splintered sparkle pattern.

Frequently Asked Questions

  1. What's the difference between an old mine elongated cushion and an old mine square cushion?
    Only the shape. Both are old mine cuts with the same faceting, high crown, small table, and open culet. A square old mine cushion has a length-to-width ratio of about 1.00–1.10; an elongated one runs 1.15–1.40 or longer, giving a finger-lengthening look that often appears larger per carat.

  2. What length-to-width ratio counts as "elongated"?
    By antique standards, anything above ~1.10 reads as elongated. Soft elongation is ~1.20–1.30; dramatic, rectangular looks reach 1.40–1.50. Lab-grown stones can be cut to your exact preferred ratio.

  3. Do old mine cushion cuts sparkle?
    Yes, with broad, chunky flashes and strong colored fire rather than fast white glitter. They were designed to glow in candlelight, so they look their best in warm, directional light.

  4. Is an old mine cushion the same as a modern cushion?
    No. A modern cushion has precise symmetry, a small or closed culet, and faceting tuned for electric light (often "crushed ice"). An old mine has a high crown, smaller center area, and an large culet, producing a warmer, chunkier candlelight glow.

  5. Can you get a lab-grown old mine elongated cushion?
    Yes. Lab-grown is actually the easiest way to get the rare elongated silhouette, in untouched condition, with IGI certification and at a more accessible price point than antique. Ouros offers both square and elongated lab-grown old mine cushions.

  6. Are old mine cut diamonds worth more?
    Among antiques, well-preserved larger stones and elongated examples especially can command premiums due to rarity. Among lab-grown, both shapes are priced by the 4Cs and carat, so value is driven by quality, not scarcity.

  7. Which looks bigger, square or elongated?
    Elongated usually looks larger for the same carat weight because the stone's surface area is stretched along a longer axis.

  8. What metal is best for an old mine cushion?
    Yellow gold is the classic, most flattering choice for warm antique tones; rose gold is a warm middle ground; white gold/platinum suits higher-color lab-grown stones.

  9. Why are elongated old mine cuts suddenly popular?
    High-profile celebrity engagement rings featuring elongated old mine cushions revived mainstream interest in a silhouette that's genuinely rare in antiques, which is why lab-grown versions have surged in demand.

  10. How do I tell a true old mine cut?
    Look straight down through the table: a small circle (the open, flat-ground culet) is the classic giveaway, along with a high crown and a small table relative to the diameter.

Next article The Complete Guide to Lab-Grown Diamond Jewellery: Ethical Luxury for Modern Couples

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