Old Mine Cut Diamond
The old mine cut is the predecessor to the modern cushion brilliant, cut by hand before electric tools existed. It features a high crown, small table, large culet, and chunky facets that produce a warm, romantic light pattern entirely different from modern precision cuts.
Is a old mine cut diamond a good choice?
Old Mine Cut diamonds are known for moderate brilliance with 58 facets. They're popular for vintage-style engagement rings and antique restoration. Here are the trade-offs.
Why people love it
- +Every stone is one-of-a-kind with unique character
- +Warm, romantic light pattern that comes alive in candlelight
- +Sustainable choice. Recycled antique stones, no new mining.
- +Often more affordable than modern equivalents at the same carat weight
- +Broad, chunky fire that modern precision cuts cannot replicate
Things to know
- −Faces up smaller than modern cuts of the same weight (more depth, less spread)
- −No standardized grading. You need experience or a specialist to evaluate.
- −Condition varies. Some stones have chips or abrasion from age.
- −Limited supply. Finding specific sizes takes patience.
How big is a old mine cut diamond? (MM to carat)
A 1-carat old mine cut diamond measures approximately 6.2 x 6.2 mm. Here are the most common sizes from 0.25 ct to 5 ct.
| Carat Weight | Size (mm) |
|---|---|
| 0.25 ct | 4 x 4 mm |
| 0.33 ct | 4.3 x 4.3 mm |
| 0.5 ct | 5 x 5 mm |
| 0.75 ct | 5.6 x 5.6 mm |
| 1 ct | 6.2 x 6.2 mm |
| 1.25 ct | 6.5 x 6.5 mm |
| 1.5 ct | 7 x 7 mm |
| 2 ct | 7.5 x 7.5 mm |
| 2.5 ct | 8 x 8 mm |
| 3 ct | 8.5 x 8.5 mm |
| 4 ct | 9.5 x 9.5 mm |
| 5 ct | 10.5 x 10.5 mm |
View full old mine cut size chart → with all sizes from melee to 5+ carats.
How to buy a old mine cut diamond
- •Buy from dealers who specialize in antique diamonds. General jewelers often undervalue them.
- •Inspect the culet size. A small culet is desirable. An overly large culet dominates the face-up view.
- •Check for chips and abrasion on the girdle and facet edges. Minor wear is expected but heavy damage affects beauty.
- •Evaluate the symmetry of the cushion outline. Slight asymmetry adds charm but major lopsidedness is a flaw.
- •Color below J-K can actually be desirable in old mine cuts: the warmth suits the cut's character in period settings.
- •Request photos in multiple lighting conditions. Old mine cuts look completely different under direct light vs. diffused light.
What makes a old mine cut diamond unique?
Old mine cuts dominated diamond jewelry from roughly the 1700s through the early 1900s. Every stone was cut by hand, using the natural octahedral shape of rough diamond crystals as a starting point. Cutters prioritized weight retention over light performance, which is why old mine cuts have distinctly different proportions from modern stones.
The defining characteristics are a small table facet (typically 40-55% of the stone's width, compared to 55-62% in modern cuts), a steep crown angle, and a visible culet (the flat facet at the bottom point, which appears as a small circle or square when viewing the stone face-up). The overall outline is a soft, squarish cushion shape with gently rounded corners.
Because each stone was hand-cut, no two old mine cuts are identical. They exhibit natural asymmetry and character. Rather than the precise pinpoint scintillation of a modern brilliant, old mine cuts produce broad, chunky flashes of light and warmth. Under candlelight (which is what they were designed for), they come alive with deep fire that modern cuts can't replicate.
The market for old mine cuts has grown significantly in recent years. Buyers are drawn to the romance, history, and sustainability of antique stones. Prices vary enormously based on the stone's condition, proportions, and whether the faceting is attractive. Well-proportioned old mine cuts in good condition command premiums over generic antique diamonds.
How much does a old mine cut diamond cost?
Old Mine Cut diamonds are priced at highly variable. well-cut examples can match or exceed modern cushion prices. average examples are 20-40% below modern equivalents.. Price depends on carat weight, color, clarity, and cut quality. For a personalized estimate, use our diamond price estimator.
Estimate old mine cut diamond price →Technical Specifications
- Facets
- 58
- Brilliance
- moderate
- L:W Ratio
- 1.0:1 to 1.15:1 (squarish cushion, often slightly off-square)
Last updated: 2026-07-16
At a Glance
- Price vs Round
- Highly variable. Well-cut examples can match or exceed modern cushion prices. Average examples are 20-40% below modern equivalents.
- Popularity
- Niche but growing. Sought after by vintage jewelry enthusiasts and sustainability-focused buyers.
- Sparkle
- moderate
Best For
vintage-style engagement ringsantique restorationbezel and low-profile settingsyellow/rose gold settings (the warmth complements the cut)collectors and sustainability-focused buyers
Setting Ideas
- Bezel: protects edges and complements the vintage aesthetic
- Low-profile solitaire: lets the stone's character take center stage
- Yellow or rose gold: warm metal enhances the cut's inherent warmth
- Milgrain or engraved band: pairs the antique stone with period-appropriate metalwork
- Collet setting: historically accurate, simple round bezel used in the original era