The Lustrous Legacy of Diamond Manufacturing

Last week I began a new series of articles that continues our journey through the diamond pipeline with a new focus on the midstream manufacturers.  We looked briefly at how diamonds are cut, and I touched on how manufacturers choose their rough and what they do to manufacture different types of rough diamond models.  Before we go further into looking at the manufacturing industry and what drives it, I want to look at how the industry developed in the first place.  Entire books could be written on the history of the diamond industry (and several have been), but I want to look briefly at the origins of diamond cutting. 

By looking at how, and where diamond cutters have built their business, both past and present, perhaps we can gain some new insight into where the industry might be headed. 

The First Diamond Cutting

Exactly when diamonds were first discovered is still a mystery.  The story of Exodus 28:18 refers to diamonds, amongst other gemstones.  However, there appears to be some confusion in part due to the erroneous translation of the Hebrew word yahalom into the Greek word adamas. Yahalom is derived from halam, which means to beat; whereas the Greek word adamas means invincible.  These words appear from time to time in pre-biblical era writings and have been ascribed to refer to diamonds.  Although we can’t be entirely sure that early writings did in fact refer to diamonds, there is suggestion from as far back as 300 B.C. that the gems had been discovered and were coveted for their hardness properties.  In these early times and the centuries that followed, diamonds were believed to protect their owner from harm, and transforming diamonds in any way by cutting them would probably have been considered sacrilege.   The Ratnapariska of Buddhabhatta, a Sanskrit manual on gems dating from about 500 A.D., states: “He who wears a diamond will see dangers recede from him, whether he be threatened by serpents, fire, poison, sickness, thieves, flood or evil spirits.”

Diamonds were especially coveted by the Romans and were prized for use in jewelry, some of which survives today and can be found on display in galleries around the world.  However, these diamonds would not be cut in any way, as techniques and knowledge of how to do this would take centuries to develop.  Pliny the Elder wrote about diamonds in his work Naturalis Historia, Pliny detailed how a diamond’s “hardness is beyond all expression,” but also appears to have understood that diamonds could be cleaved if force was applied at particular angles.

As we now know, diamonds can only be polished using other diamonds.  However, exactly when this knowledge was first discovered is in dispute.  The Agastimata, an Indian text believed to have been written shortly after the 13th century AD, notes the following: “The diamond cannot be cut by means of metals and gems of other species; but it also resists polishing, the diamond can only be polished by means of other diamonds.”  However, the Ratnapariska, written hundreds of years earlier, states:  “Wise men should not use a diamond with visible flaws as a gem; it can be used only for polishing of gems, and it is of little value.”

Despite this understanding, early diamond cutting would have been an extremely time consuming task using crude tools, such as bow drills or leather straps bonded with diamond powder.  Since the earliest diamonds would have been reserved for only the very wealthiest in the world, slaves would surely have done this cutting, such that time was of no concern to the diamond’s owner.

The first diamonds were mined exclusively in India for many centuries.  It is believed that most of the largest and most important diamonds were kept inside the country by the Indian elite. These diamonds include the Hope Diamond, Koh-i-noor, and the Great Mogul Diamond.  Indian artisans would necessarily have developed the skills to cut diamonds, and this is supported by texts including the Agastimata; however, it isn’t clear how many diamonds were actually cut, and how many were left in the natural rough form.

Diamonds Arrive in Europe

It was around the 14th century that trade routes from India opened up into Europe.  Since the highest quality diamonds would have been kept inside India, the Islamic middlemen and caravan traders of the day would likely have picked the few nice stones that may have been smuggled out.  It is entirely possible that the practice of cutting diamonds in Europe developed because the highest quality diamonds were not shared with them, and they were forced to make do with the lower quality rough diamonds to which they had access.  These diamonds would have needed to be cut in order to bring out their brilliance.  Whatever the reason, Venice would become a hub of diamond trading and manufacturing sometime after 1330.

Many Venetian traders began bringing diamonds to the Flemish town of Brugge in Belgium, at the end of the trade route from Venice following the Rhine River.  There, in the mid-1400s, legendary Flemish inventor Lodewyk van Bercken developed the scaife, which would change diamond cutting forever.  Van Bercken’s scaife consisted of a rotating disk covered with a thin layer of olive oil mixed with a compound of diamond dust.  By fashioning the diamond into a dop and applying it against the rotating diamond grit, facets could be cut into the diamond and any desired shape could be achieved.  Modern versions of his invention remain in use today as the primary tool for faceting diamonds.

While Brugge would develop into a diamond-cutting centre for a brief time, the nearby port city of Antwerp would be seen as a better fit.  Antwerp was already an established trading post and port for Portuguese and Spanish ships.  Antwerp would help to increase access to diamonds for Europe’s elite after the Portuguese conquered the Indian port city of Goa in 1510 and developed it into a main diamond shipping port.  Antwerp would remain at the centre of European diamond trading and manufacturing for decades.  However, after the Spanish attacked Antwerp in 1585, most Antwerp diamond cutters headed north to nearby Amsterdam where they re-established the trade in Holland.  

Amsterdam would grow as a cutting centre in large part due to the influx of Sephardic Jews who settled in the city after leaving the Iberian Peninsula, as well as those who fled Antwerp after the Spanish invasion.  The merchant guilds of the day did not accept Jewish members so the population looked to non-traditional trades for employment.  The relative peace of Amsterdam would allow the industry and the cutting technology of the day to flourish there.  It is apparent from Anselmus de Boodt’s Gemmology and Lapidary Science (1600) that techniques for cleaving, bruting, faceting, and polishing were already in use by that time.

New Supply

At that time, diamonds had still only been discovered in India and mining techniques were crude by today’s standards.  The diamond trade was reserved only for the ultra-wealthy, mostly European royalty, and supply was limited.  The small industry would get a big boost in the early 1700s when workers panning for gold in the Rio Dos Marinos riverbed first discovered diamonds in Brazil.  As legend goes, the shiny stones had been discovered earlier but workers failed to recognize them and they were often used as chips in card games.  It was not until 1725 that a Portuguese man named Sebastião Leme do Prado, who had once lived in India, recognized the stones as diamonds. 

These unusual stones began to show up in trading posts in Lisbon and caught the attention of Portuguese traders.  By 1728, the government of Portugal would claim these diamondiferous areas as crown property and established mining communities in the Serro do Frio district.  With more modern mining capabilities and plentiful diamond resources, Brazil’s supply of the gems would dwarf that of India and prices for rough stones would fall by as much as 70%.  This meant that while still rare and expensive, diamonds were no longer only available to kings and queens and could be afforded by European nobility.

The diamond manufacturing industry received a significant boost as a new supply entered Europe, believed to be as large as 50,000 carats a year by the late 1700s.  This influx came at a time when Indian mines were quickly depleting, making Brazil the world’s largest diamond supplier.  For manufacturers, this meant more demand for their work, and also more demand for innovative cuts and jewelry styles to suit a broader audience.  This new supply, coupled with more advanced cutting techniques, spawned a variety of new diamond cuts that began to resemble today’s modern brilliant cuts.  

The Birth of Brilliance

Prior to the invention of the incandescent light bulb in 1879, lighting of one’s home was done primarily by candle or oil lantern.  Diamond cuts were developed in a way that maximized the fire and brilliance under candlelight, which often meant small tables and large culets that would allow the soft light to filter through the diamond.  Cuts like the old European cut, the old mine cut, and the antique cushion cut (sometimes known as the pillow cut) would define how diamonds would be shaped from the early 1800s through to the start of the 20th Century.  While the cutting of these stones would have been more time consuming in the 1800s than it would be today, the process of faceting the stones would not have been fundamentally different than it would be in a modern day polishing factory.  In fact, even today, there are many people who prefer the more subtle light refraction from these older diamond cuts and there are companies who have built their businesses around re-selling these distinctive diamond styles.

The European cut was the precursor to the modern brilliant cut; however, it would not be until 1919 that Marcel Tolkowsky, a member of the prominent Tolkowsky diamond family in Antwerp, would establish the cutting proportions for the ideal cut round brilliant diamond in his book, Diamond Design:  A Study of the Reflection and Refraction and Refraction of Light in a Diamond. These ideal proportions have largely stood the test of time and the ideal cut remains the standard in the industry nearly 100 years later, and has spawned other modern brilliant shapes, such as the pear, cushion, marquise, and oval.  

Today, diamond cutting in Europe is all but extinct, and only a select few manufacturing businesses remain in cities like Antwerp or Amsterdam, which I will explore in more detail in another article.  In the past century since Tolkowsky’s work, technology has continued to enter the industry such that many time-consuming tasks in diamond manufacturing have been automated and are now done with precision by machines.  However, the fundamentals of diamond cutting remain the same as they have been since then, namely to extract the most possible beauty and value from each rough diamond.   

The views expressed here are solely those of the author in his private capacity. No one should act upon any opinion or information in this website without consulting a professional qualified adviser.