antique cut diamonds: all you need to know
(plus 5 reasons to love them hard)

There are a range of cutting techniques that fall under antique cuts. Let’s start with the oldest one: the polki diamond. Polki diamonds supposedly go back 2,500 or even 3,000 years to India, the motherland of all diamonds long before Western cutting methods were seen there. They often retain their original rough form and have an unfaceted, polished surface. Polki diamonds are often described as uncut, because of their polished planes rather than facets. The stone is generally small with a flat bottom, similar to diamond slices, but much thicker. Though they lack brilliance and fire, polki cuts do give a soft sheen. 

Polki diamonds ooze a raw, rustic, old-world charm. They tend to be cloudy, included, lower color grade and without the faceting that gives diamonds their brilliance and appeal. They’re less valuable than ordinary cut diamonds. 

Is polki diamond jewelry worth buying? The diamonds themselves don’t have much resale value, it’s the jewelry that’s time-consuming and needs a lot of skill. Polki diamonds are often used in multiples rather than a solitaire like the modern brilliant cut diamond. And since each stone has a unique shape, each setting is crafted individually. 

Once it was understood that only diamonds can cut a diamond, the process of changing the shape of a diamond began. By the 1500s, people started cutting rose cut diamonds, which have flat bottoms and a domed top. Kind of like an upside down stone, or a crown without a pavilion. Since there’s no pavilion, if the diamond has good clarity you can look right through the stone. Rose cut diamonds glow more than the minimalist and rough polki cut diamonds. But they’re still far from the brilliant diamond cuts we know today. Nowadays, rose cut diamonds are popular for their multifaceted tops, excellent finger coverage and availability of shapes. 

The single cut diamond is one of the earliest and most basic of cuts, dating back to the 1600s. The single cut was a big step forward in diamond cutting and is a very simple form of the round cut diamond. It has an octagonal girdle (the side edge of the diamond). The single cut is also known as an “eight cut” and sometimes referred to as “huit huit”, from the French “huit”, meaning eight. That’s because it’s designed with eight facets on the crown, eight facets on the bottom half of the diamond, and generally an additional single table facet on the top of the crown, making it a total of 17 facets.

Single cut diamonds can be identified by their large, flat table (the surface on the top of the stone). These days, single cut diamonds are generally used as side stones or low-cost diamond jewelry like watch dials, tennis bracelets, earrings and gemstone jewelry. They complement colored stones like emerald, garnet, ruby and kyanite, because the single cut reveals a whiter color that helps accentuate these stones more fully, without all the distracting fire of a modern diamond. 

Fast forward two centuries later, cutting skills and techniques had evolved, but lighting conditions hadn’t. Diamonds were still cut by hand, with cutters using only their eyes and dim light or daylight to measure the precision of their work. 

To level up the refraction factor, jewelers started making the bottom part of the diamond longer and the culet slightly more pointy. This way, light could travel further and bounce back and forth inside the diamond, creating ‘fire’. This was the first attempt to create a diamond cut shining for centuries. Shape consistency and symmetry was of less importance than play of light.

The first generation of brilliant cuts is the old mine cut, popular in the 1700s. The old mine cut still has a larger and wider culet, because no technology existed to make a pointy tip (yet). It also has a shorter bottom half, imperfect facets and asymmetrical features, all thanks to the hand cut nature of the old mine cut. The result is more sparkle and brilliance than a rose cut diamond. If you look at an old mine cut diamond from the side, you might find the girdle to be thick and occasionally unpolished.  

Old mine cut diamonds come in many shapes and proportions. Most old mine cut diamonds have a pillow cushion shape, as the cut follows the shape of the octahedral diamond crystal to retain as much of the weight of the rough as possible. Old mine cut is the nomenclature given to all older diamonds with a brilliant cutting style, no matter their shape. Their shapes can range from almost square with rounded corners, to oval and to pear. Irregular shapes are also found, these are called a crude old mine cut. 

Enter the late 19th century for the second generation of brilliant cut diamonds: the old European cut (old Euro cut or OEC). This Art Deco darling has a smaller culet than the old mine cut, but it’s still very much noticeable and far from the pointy modern diamond. You get better refraction of light and more colors, but with its deep pavilion, small table and tall crown, it’s still unlike the brilliant cut we know today. If you see it from the top, you’ll see a rounded crown instead of the cushion shape of the old mine cut. From the side, you’ll find the girdle to be smaller than the old mine cut. In other words, we’re getting closer to brilliant cut diamonds! 

The main difference between polki and rose cut diamonds lie in the pattern of facets. Polki diamonds tend to have a handful or less of large, flat facets. They’re not necessarily faceted, but polished to retain their natural structure, often into an irregular and asymmetrical form as the cutter strives for the maximum size. Facets in rose cut diamonds have more of a pattern and more of a crown.

Although both may be imperfectly shaped, you’ll find rose cut diamonds tend to be less asymmetrical than polki diamonds, which fully follow the raw diamond’s shape. 

The shape of the old mine cut vs cushion cut can be confusing. Both cuts have slightly rounded, curved sides with a pillow-like appearance, and the old mine cut is considered the precursor of the modern cushion cut. But, where the cushion cut only comes in square and rectangular shapes, the old mine cut may also be pear, marquise or triangle shaped. 

The key difference between the two is the way they are cut. The old mine cut uses primitive processes under low lighting conditions, resulting in wonky shapes and uneven facet sizes. There were no standards for the shape, and cutters attempted to save as much of the diamond weight as possible. As compared to the modern cushion cut, old mine cut diamonds have a smaller table, taller crown, deeper pavilion, chunkier facets and open culet rather than a pointy tip. 

Modern cushion cuts aim for symmetry, color retention and play of light, meant to sparkle under electric light. The culet got so small to the point it disappeared, the table got wider, the crown lower, the pavilion more shallow and the facets smaller and more elongated. It’s significantly lower profile than the old mine cut. 

Both the old mine and cushion are brilliant cuts, but they react to light differently. The different facet shapes and sizes makes the old mine cut show larger face-up patterns of light and dark and less brilliance than the modern cushion cut. 

Placed next to a modern diamond, the proportions of an old mine cut diamond can look overly large and bulky at first glance. It’s only under candlelight that you see its soft, romantic glow. 

The main difference between the single cut and modern brilliant cut diamond is in the number of facets. This affects the appearance and price of the diamond. A single cut diamond only has 16 to 18 facets, whereas a full-cut diamond has 57 or 58 facets. The high number of facets maximizes light reflection, giving the diamond more brightness and brilliance as compared to a single cut diamond. Needless to say, a full cut costs more time, and so more money.

The modern cut makes the diamond look significantly nicer than a single cut - to the point I’ve heard a gemologist say the single cut is an insult to a diamond’s beauty and brilliance. With modern day technology it’s not that much costlier, so these days only some melee diamonds (these are small diamonds, usually under 0.12 ct used as sparkly accents) still use the single cut to save money. 

In terms of looks, the light reflection in a full cut diamond is much higher than in a single cut, so a single cut diamond has less brilliance and shine. 

While single cut diamonds have a decidedly vintage look and were very popular between the 19th century and mid 20th century, they are rarely used as the center stone these days. 

The Old European cut has a smaller table, higher crown with a steeper angle, deeper pavilion and a larger culet than the modern round brilliant cut. The modern round brilliant cut is designed to push its fire and brilliance up through the middle of the stone. The Old European cut looks less brilliant from the top down view, yet offers more brilliance and fire from the side.