A friend of a friend says the ring their fiancee is giving them is quite expensive because it has "miner" cut diamonds. Is this true?
It's "old mine cut."
This cut of diamond was prevalent in the 1800's up until the time in which the Old European cut diamond took over. Vintage stones can be worth more that modern cuts--not so much because of the cut as it is because of the quality of the stone. A very well cut Old Mine Cut stone is quite brilliant. Lots of diamonds that are faceted and set these days would have been put in drill bits years ago. The modern cuts have been developed to take full advantage of the diamond's natural refractive characteristics.
Vintage cuts used to be a disadvantage (and sometimes still is) when valuing a diamond, but in recent years, antique cuts and ring mounts have become a popular choice for engagement rings. This new market drives the pricing of old diamond rings. Your friend's ring is probably comparable in price to a modern ring with the same diamond weight.
There are some beautiful old mine cut on eBay right now. Have a look:
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 Vintage 0.12 ct Old Mine Cut Loose Diamond SI2 G $99.99 Time Remaining: 7h 34m Buy It Now for only: $99.99 |
 1.51 carat old miner old mine cut loose diamond new $5,350.00 Time Remaining: 15h 33m Buy It Now for only: $5,350.00 |
 1.01 carat old miner old mine cut loose diamond new $2,850.00 Time Remaining: 16h 39m Buy It Now for only: $2,850.00 |
 2.01 carat old miner old mine cut loose diamond new $8,975.00 Time Remaining: 1d 46m Buy It Now for only: $8,975.00 |
 Rare Lot Old European and Old Mine Cut diamonds 5.92 ctw $7,350.00 Time Remaining: 1d 5h 5m Buy It Now for only: $7,350.00 |
 old miner 1.75 carat cut loose diamond old mine new $7,870.00 Time Remaining: 1d 8h 3m Buy It Now for only: $7,870.00 |
 Old mine 2 carat loose diamond old miner cut new $8,475.00 Time Remaining: 1d 9h 13m Buy It Now for only: $8,475.00 |
 Gorgeous old mine diamond old miner cut loose 2 cts. $8,975.00 Time Remaining: 1d 22h 5m Buy It Now for only: $8,975.00 |
 Gorgeous old mine diamond old miner cut loose 2 carat $8,975.00 Time Remaining: 2d 6h 23m Buy It Now for only: $8,975.00 |
 Old mine 2 carat loose diamond old miner cut new $8,475.00 Time Remaining: 2d 15h 1m Buy It Now for only: $8,475.00 |
 Old miner old mine cut loose diamond 2.51 carat diamond $12,500.00 Time Remaining: 3d 58m Buy It Now for only: $12,500.00 |
 1.67 ct Old Mine Cut Fancy Color Yellow VVS2 GIA Certified Loose Diamond $10,020.00 Time Remaining: 3d 2h 58m Buy It Now for only: $10,020.00 |
 old miner 1.75 ct. cut loose diamond old mine new $7,870.00 Time Remaining: 3d 3h 58m Buy It Now for only: $7,870.00 |
 1.01 carat old miner old mine cut loose diamond new $2,850.00 Time Remaining: 3d 6h 49m |
 Big 2.51 carats old mine cut loose diamond new $12,500.00 Time Remaining: 3d 11h 28m Buy It Now for only: $12,500.00 |
 .86 VVS J-K LOOSE DIAMOND ROUND OLD MINE CUT SEE VIDEO! $599.00 (1 Bid) Time Remaining: 3d 23h 50m |
 1.75 carat H/I VS1 old miner old mine cut loose diamond $7,875.00 Time Remaining: 4d 2h 54m Buy It Now for only: $7,875.00 |
 3.01 Ct. H/I VS1 loose diamond old miner old mine cut $16,750.00 Time Remaining: 4d 8h 32m Buy It Now for only: $16,750.00 |
 2.01 carat old miner old mine cut loose diamond new $8,975.00 Time Remaining: 4d 8h 36m Buy It Now for only: $8,975.00 |
 1.25 ct. G/H VS1 old miner old mine cut loose diamond $4,585.00 Time Remaining: 4d 19h 9m Buy It Now for only: $4,585.00 |
 Gorgeous old mine diamond old miner cut loose 2 carat $8,975.00 Time Remaining: 4d 21h 36m Buy It Now for only: $8,975.00 |
 Old miner old mine cut loose diamond H/I VS1 2.01 carat $8,475.00 Time Remaining: 4d 22h 48m Buy It Now for only: $8,475.00 |
 3.07 ct Old Mine Cut Fancy Faint Color GREENISH YELLOW Yellow SI2 GIA Diamond $17,775.30 Time Remaining: 5d 7h 37m Buy It Now for only: $17,775.30 |
 1.03ct Old Mine Brilliant Cut J/VS1 GIA Uber Solitaire R4323 Diamonds by Lauren $6,995.00 Time Remaining: 10d 7h 44m Buy It Now for only: $6,995.00 |
 OLD MINE ANTIQUE CUT DIAMOND .61CT, CLARITY IS VS-2, COLOR IS I-J, 4.8MM X 4.3MM $856.00 Time Remaining: 10d 12h 31m Buy It Now for only: $856.00 |
 Vintage 0.14 ct Old Mine Cut Loose Diamond SI1 I $69.99 Time Remaining: 12d 23h 47m Buy It Now for only: $69.99 |
 GIA .72ct Old Mine Cut Round Loose Diamond M, SI1 $1,049.00 Time Remaining: 15d 5h 53m Buy It Now for only: $1,049.00 |
 ANTIQUE 89 PT. OLD MINE CUT DIAMOND I COLOR, I1 CLARITY $1,695.00 Time Remaining: 16d 6h 6m Buy It Now for only: $1,695.00 |
 GIA 2.43ct Old Mine Cushion Cut Loose Diamond S-T, SI1 $5,800.00 Time Remaining: 22d 7h 20m Buy It Now for only: $5,800.00 |
 Vintage 0.35 ct Old Mine Cut Diamond SI1 L $389.99 Time Remaining: 29d 14h 7m Buy It Now for only: $389.99 |
It's "old mine cut."
This cut of diamond was prevalent in the 1800's up until the time in which the Old European cut diamond took over. Vintage stones can be worth more that modern cuts–not so much because of the cut as it is because of the quality of the stone. A very well cut Old Mine Cut stone is quite brilliant. Lots of diamonds that are faceted and set these days would have been put in drill bits years ago. The modern cuts have been developed to take full advantage of the diamond's natural refractive characteristics.
Vintage cuts used to be a disadvantage (and sometimes still is) when valuing a diamond, but in recent years, antique cuts and ring mounts have become a popular choice for engagement rings. This new market drives the pricing of old diamond rings. Your friend's ring is probably comparable in price to a modern ring with the same diamond weight.
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