Old Cut Diamonds: OMC vs OEC, value & buying guide

In today’s diamond world, one cut dominates: the modern round brilliant. But it wasn’t always this way.

Before the 20th century brought standardised proportions and calibrated stones, diamonds were cut by hand. Cutters worked to the shape of the rough, guided by experience and artistry rather than strict 'ideal' measurements. The result? A fascinating family of diamonds now known as old cut diamonds (also called antique cut diamonds or old cuts), each with its own personality.

Old cut diamonds were created in a time when cutters prioritised retaining rough diamond weight over uniformity. That’s why antique cuts often have charming quirks: slightly uneven facets, taller crowns, deeper pavilions, and visible culets. These features create the look old cut lovers adore - bigger, chunkier facets and a warm sparkle that can feel especially beautiful in softer light (e.g: candlelight, lamplight, and golden hour).

Today, old cuts are sought after by collectors and by those wanting a truly unique antique engagement ring with history, character, and romance.

What is an old cut diamond?

An old cut diamond is a diamond cut in an earlier style, typically before modern precision cutting became widespread. 'Old cut' is an umbrella term covering several antique diamond cuts, including old mine cuts, old European cuts, rose cuts, and single cuts.

Because these diamonds were cut by hand (often to suit the individual rough), no two are quite the same - and that individuality is part of the magic.

The main types of old cut diamonds

	Rose cut diamond A rose cut has a flat base with a domed top covered in triangular facets (rather than a full pavilion underneath). Rose cuts were often used to maximise thin pieces of rough created through cleaving. Facet counts vary widely - from very simple early examples to more complex versions. You’ll often see rose cuts as accent stones, but a larger rose cut can make a stunning centre stone with a softer, luminous 'glow'.
	Single cut or eight cut diamond  A single cut is a simple early cut, typically seen in smaller diamonds - especially in antique halos, shoulders, and delicate details. Single cuts generally have fewer facets than modern brilliant cuts, which can make them look crisp and bright for their size. Some older single cuts also show a tiny culet (a small facet at the tip).
	Old mine cut (OMC) diamond The old mine cut (often abbreviated OMC) is commonly cushion-shaped, with a higher crown, a noticeable culet, and bold, chunky facets. Old mine cuts can be wonderfully individual - slightly irregular outlines and quirky proportions are part of the charm. You’ll often find OMC diamonds in Victorian and Edwardian era jewellery - they're a favourite for anyone who loves a true antique look. You may also see them referred to as an 'Old Brilliant' or 'Old Miner'.
	Old European cut (OEC) diamond  The old European cut (often abbreviated OEC) is rounder and is often considered the bridge between old mine cuts and the modern round brilliant. OEC diamonds tend to have more even facet placement, a smaller table, and a culet that can still be visible - usually less prominent than many OMCs. OEC diamonds are loved for their romantic, 'chunky' sparkle and are especially popular in antique and vintage engagement rings.

 

Old mine cut vs old European cut: How to tell the difference

Old mine cuts (OMC) and old European cuts (OEC) can overlap in age and both have that beautiful antique sparkle. A few visual clues can help you tell them apart.

Old mine cut (OMC) - typical clues

• Outline: Usually cushion-ish (softly square/rectangular with rounded corners), not perfectly round
• Facet pattern: Bold, chunky facets with more 'handmade' variation
• Shape personality: Often a little wonky/individual (part of the charm)
• Table and crown: Often a broader table with a higher crown, with more height in profile
• Culet: Often noticeable face up (a small 'window' in the centre)
• Overall vibe: Big flashes and a warm glow 

Old European cut (OEC) - typical clues

• Outline: Generally rounder overall than an OMC
• Facet placement: More even and symmetrical - a step closer to modern cutting
• Table and crown: Often a smaller table with a high crown
• Culet: Usually smaller than many OMCs, but can still be visible face up
• Overall vibe: Romantic, balanced sparkle

Do old cut diamonds sparkle?

Yes - but differently from modern brilliants.

Modern round brilliants are optimised for bright, splintery scintillation under strong lighting. Old cuts often have larger facets and different proportions, which can produce broader flashes of light. Many people love how old cuts look in real life lighting - softer, warmer environments where they can glow and flicker beautifully.

How old cut diamonds are valued

Like modern brilliant cut diamonds, the value of old cut diamonds is influenced by the 4Cs (carat, colour, clarity, and cut), but with a more forgiving view of cut and clarity. With antique diamonds, small quirks and individuality are often part of the appeal.

There’s also a key difference: while many modern diamonds are commonly priced against industry guides (such as Rapaport), old cut diamonds are valued more as individual stones, with pricing heavily influenced by rarity, character, and overall beauty rather than strict 'ideal' proportions.

Rarity: colour, size, and unique antique cuts

Fancy colour old cut diamonds are highly desirable due to their rarity. Fancy brown and yellow old cuts can be found from time to time and are prized by collectors. The most sought after colours are blue and red. One famous example is the Hope Diamond - a fancy greyish-blue old mine cut that is one of the most famous diamonds in history.

Larger old cut diamonds (especially over 1 carat in size) are also hard to come by, and there are a few reasons:

• Diamond jewellery (especially diamond engagement rings) became much more popular in the 20th century. By then, many old cut diamonds were already sitting in jewellers’ inventories.
• For decades (even until relatively recently), the fashion was to recut old diamonds into modern round brilliants.
• Recutting typically means losing carat weight, so larger old cuts were often the first to be recut.

Because of this, well-preserved larger old cuts can be rare today - especially in higher colour and clarity.

Unique shapes can also command a premium, such as old pear cuts or the famed Peruzzi cut. Fancy shapes are generally harder to facet than round cuts, which adds to their scarcity.

Other factors can influence value too, including kozibe (internal reflections seen in some antique cuts). 

Most importantly, overall beauty matters rather than just strict numerical proportions.

Why 'imperfections' can add value in old cuts

Features that would lower the value of a modern cut - like slightly asymmetrical facets, a deeper pavilion, or a higher crown - can add desirability in old cut diamonds. These variations often contribute to the distinctive, romantic sparkle old cuts are loved for.

Buying tips: what to look for in an old cut diamond

When choosing an antique cut diamond, it helps to focus on what matters most face up:

• Light performance you love: Big flashes vs glittery sparkle
• Culet visibility: Some people love a visible culet, others prefer a more subtle look
• Facet pattern: The larger and more asymmetrical facets are part of the appeal
• Condition: Look for major factors that may affect durability, but a lot of the time these older diamonds display minor chips/nicks that do not affect beauty/wear
• Setting style: Antique settings can change the way a diamond presents
• Overall beauty: With old cuts, the best stone isn’t always the one with the 'best numbers'

Old cut diamonds are a wonderful reminder that nature and craftsmanship don’t have to be perfectly uniform to be breathtaking. These stones have survived changing tastes for a reason - they capture light in a way that feels alive, warm, and full of history. They’re also becoming increasingly rare to find today.

Ready to find your perfect old cut diamond ring? Explore our diamond jewellery collection here.