• Antique Animal Jewelry

Antique Gemstone Guide: Diamonds

Diamonds. They are forever; they are a girl’s best friend; they are the coal that did well under pressure. Is there a more iconic gemstone? Probably not.

But – why? What makes diamonds so special?

The very word ‘diamond’ comes from the Greek ‘Adamas,’ meaning invincible. Diamonds have always been known for their hardness.

Diamonds are made of pure carbon, with a unique atomic structure that makes them extremely hard and durable. Essentially, diamonds are extremely rare, and as a general rule, rarity adds value.

How are diamonds formed?

There are many similar sayings along the lines of ‘diamonds are the coal that did well under pressure.’ This is partly true. Diamonds are formed in the earth’s mantle, under intense pressure and heat. Over time, they are brought up towards the earth’s crust by deep volcanic eruptions.

However, it is a common misconception that diamonds are made of coal. Many scientists believe that most of the earth’s diamonds were formed before coal was even around. It’s not fully known exactly where the carbon comes from that forms diamonds, but it’s likely from pre-existing minerals in the earth. Most naturally occurring diamonds date back billions of years.

'Raw' diamonds - diamonds that have not yet been cut for jewelry. Three diamonds in this image form natural octahedrons.

A History of Diamond Cuts

Cut is something that has affected diamonds' shine and style for as long as they have been worn by people. It is essentially how the diamond is cut in order to allow it to reflect the most light. AKA, it's how diamonds get that sparkle.

The Point Cut

Diamonds that crystallized in natural points have been admired for millennia. In Ancient Rome, these were the preferred shape for diamonds. Up until about the 15th century, in fact, diamonds weren't cut at all, only polished to emphasize their natural points. From the 15th century onwards, diamond cutters would grind the stone to try and improve its symmetry and reproduce the look of a perfect natural crystal.

Until the 18th century, the only diamonds available were from India and the Golconda diamond fields. In India, naturally pointed diamonds were very valuable and considered to have lucky powers. As a result, few natural pointed diamonds left India for Europe, as they were keenly swept up by Indian collectors. The diamonds that made it to Europe often had to be cut in order to improve their appearance.

Renaissance point cut diamond ring, c.1560. Traces of black enamel. The side petals here are characteristic of later renaissance jewelry.

Photo via Diamonds: The collection of Benjamin Zucker by Diana Scarisbrick.

The Table Cut

'Table Cut' refers to any diamond with a flat top table facet. Falling into this category are mirror cuts, step cuts, scissor cuts, Peruzzi cuts, and the historical full table cut. Once people began cutting diamonds, they soon realized that the way they cut the rock changed its interaction with light. The first table cuts were essentially point cuts with a flat table cut on top. These are often seen in renaissance jewelry from the mid-1400s to the late 1600s.

Portrait diamonds usually fall under the table cut category, as they usually have flat-topped surfaces through which the portraits can be seen. Portrait diamonds were a particular feature of the late 18th and 19th centuries.

17th-century renaissance table cut diamond ring. Here, the goldsmith likely grouped five small diamonds together into a pattern in order to overcome the challengingly small size of the diamonds available.

Photo via Diamonds: The collection of Benjamin Zucker by Diana Scarisbrick.

A gothic style enameled bracelet. The centerpiece is a 25-carat portrait diamond. The miniature portrait is of Alexander I, Emperor of Russia. The Miniature was completed by Ivan Winberg (1825-46). Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

Medallion with a miniature of Alexander I, underneath a scissor-cut portrait diamond within a double diamond frame. Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

Centerpiece for a bracelet with a miniature of Alexander I, beneath a 22-carat portrait diamond. Miniature by Domenico Bossi (1757-1858).

Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

Brooch with a miniature of Alexander II under a rectangular cut diamond with a border of pink diamonds. The outer border is mounted in gold and silver with a row of antique-cut diamonds.

Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

The Rose Cut

Whilst point and table cuts were fairly minimal in editing the natural diamond, the rose cut was a more maximalist, sparkly alternative that grew in popularity from the 17th century onwards. Triangular facets allowed for extra light-catching and therefore better brilliance. The Dutch Rose cut is a specifically six-sided rose cut. In Georgian and Victorian jewelry, the rose cut abounds. From the six-faceted shape, 'crowned' twelve faceted and further eighteen faceted shapes grew in popularity for their unique sparkle.

Gold band set with rose-cut diamonds, late 17th century, on black enameled ground. The black enamel was recommended by Joseph Addison, who stated that 'the jewels appear in their true and genuine luster while there is no color that can infect their brightness or give false cast to the water.'

Photo via Diamonds: The collection of Benjamin Zucker by Diana Scarisbrick.

Portrait of Louis XIV in court dress, surrounded by two rows of rose-cut diamonds. Miniature by Jean I Petitot, c. 1680-85. Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

Foiled rose cut diamond bow-drop earrings set in silver. c. 1780.

Photo via Georgian Jewellery 1714-1830 by Ginny Redington Dawes and Olivia Collings.

Five-stone rose cut diamond half-loop ring with multiple basket settings. c.1800.

The Old Mine Cut / Cushion Cut

The cushion cut emerged in the 18th century and was also referred to as the 'mine cut,' as it rose in popularity with the discovery of new diamond mines in Brazil, just as Indian mines were becoming seriously depleted. When more mines were found in South Africa, this cut's name changed to the 'old mine' cut. It is a square cut with rounded corners.

Modern cushion cuts are different from the old mine cuts, typically with 64 facets instead of the old mine's 58. However, the two cuts are very similar and both use rounded square edges.

Gold and silver pavé set diamond ring, late 18th century. Featuring cushion and brilliant shaped diamonds with pear-shaped diamonds above and below the bezel. This ring would have covered the finger all the way up to the knuckle.

Photo via Diamonds: The collection of Benjamin Zucker by Diana Scarisbrick.

The Old European Cut

The Old European generally refers to the brilliant cuts of the 19th and 20th centuries that preceded the standard round brilliant cuts that are so unanimous today. These often refer to asymmetrical or imperfectly cut brilliant shapes, as these were hand-cut before the discovery and introduction of mechanical cutting devices. Furthermore, at the time, the Old European cut was less popular because it had the side effect of lessening the weight (carats) of the diamond.

Pendants set with miniatures of the daughters of Nicholas II and Alexandra. Surrounded by old-cut diamonds, c. 1906.

Photo via Portrait Jewels: Opulence & Intimacy from the Medici to the Romanovs by Diana Scarisbrick.

The Brilliant Cut

There is some debate about exactly when and by whom brilliant cuts were first used. The brilliant-cut is the cut we are most exposed to today and is so popular because it aims to maximize the brightness and brilliance of the diamond. Brilliant cuts are multifaceted and are generally thought to have first been seen in the 17th century. Within brilliant cuts, there are round and oval shapes as well as some more square-ish forms.

Above left: the largest green diamond in the world, the Dresden Green, at 41 carats. Mounted as a hat jewel surrounded by brilliant-cut white diamonds in 1769 by Franz Michael Diespach. Above right: badge of the order of the golden fleece, with Brazilian diamonds, rubies, and a 48-carat sapphire, 1790. Bottom: Jewel set with diamonds, rubies and emeralds, 1790.

Photo via Diamond Jewelry: 700 Years of Glory and Glamour by Diana Scarisbrick.

Gold and silver cluster with brilliant-cut diamonds, mid 18th century. Five brilliant-cut diamonds surrounded by eight similarly cut, smaller stones.

Photo via Diamonds: The collection of Benjamin Zucker by Diana Scarisbrick.

Three diamond bracelets, c. 1780-1820. The bottom bracelet features the symbol of the Order of the Golden Fleece.

Photo via Georgian Jewellery 1714-1830 by Ginny Redington Dawes and Olivia Collings.

What are the four Cs?

The four Cs are often thought of as the definitive quality rankings for diamonds – but they are actually a relatively new invention. In the 1940s, Robert M Shipley, a retail jeweler, established an institute called GIA (Gemological Institute of America) in order to formalize the jewelry industry.

The four Cs were developed to help his students remember the important characteristics of a diamond: cut, color, clarity, and carat.

Cut not only involves the shape itself but how well the diamond is cut. The GIA introduced a rating system that values perfect symmetry to create the best light retention. This scale, however, is not AAJ's favorite. The four Cs scale focuses on idealizing one type of diamond - the clearest, most perfect, symmetrical gem possible. But in antiques, inclusions and small mistakes from hand cutting add character, making each piece individual.

Color, like cut, is categorized on a scale by the GIA, ranging from pure white to yellow. The scale values lack of color as the finest standard. Again, in antique jewelry this scale did not exist, so yellowed or slightly tinted diamonds were often admired for their uniqueness.

A collection of diamonds demonstrating color variety. Photo via Understanding Jewellery by David Bennett & Daniela Mascetti.

It is rare for the strong carbon structure of diamonds to be infiltrated by other elements. However, some diamonds contain traces of other chemicals, which cause different colors to appear. For example, the presence of nitrogen gives us yellow diamonds, whilst boron can turn a diamond blue.

Clarity refers to whether or not there are 'blemishes' or inclusions, small build-ups of material interruptions in the diamond. According to the GIA scale, generally, the fewer inclusions the better. However, the GIA recognizes that certain inclusions can add value and character.

These three images show diamonds magnified up to 10 times. Each one has a unique inclusion - the Venetian mask shape, the star, and the unicorn. The Venetian mask shape is made up of a hydrogen cloud within the diamond. The star is formed from a number of pinpoint inclusions. The shape of the unicorn is formed in what is called a 'feather' inclusion. Photos via the GIA.

The last of the four Cs, carat, measures the weight of the diamond. One carat is equivalent to 200 milligrams. So generally, the higher the carats, the bigger (and more expensive) the diamond.

Why are diamonds used in engagement rings?

Diamonds are unanimous in engagement rings, but the tradition is not as old as you might think. Diamonds were not the obvious choice for engagement rings until 1947. This is when De Beers, a diamond company that owned a large portion of the market, launched one of the most iconic and effective advertising campaigns to date. They created the slogan 'a diamond is forever.'

Due to diamonds' 'invincible' nature, De Beers decided that it would be the perfect stone to represent eternal love and long-lasting marriage. Their advertising campaign focused on creating a link between love and diamonds, to try and change the public perception of the stone into one associated with romance.

The campaign was wildly successful. Diamond sales soared. De Beers then took the opportunity to market diamonds in Japan, as a symbol of Western values. According to Insider, 'when the campaign began, in 1967, not quite 5% of engaged Japanese women received a diamond engagement ring. By 1981, some 60% of Japanese brides wore diamonds.'

With two highly influential countries in both East and West going crazy for diamonds, it's little wonder that the new tradition spread globally within a matter of decades. Today, diamonds are the go-to choice for millions of engagement rings every year.

Advertisements from the original De Beers 'A Diamond is Forever' campaign.

Photo via De Beers.

Need more sparkle to feast your eyes on? See Antique Animal Jewelry's collection of diamond jewelry below:

#diamondjewelry #diamondsareforever #girlsbestfriend


Recent Posts

See All