Diamond Cutting History PDF

Ass #8 : Diamond Cutting Diamond Cutting History: -Thousands of years ago, people considered diamond rough too sacred to cut or shape. They believed that tampering with it would destroy its supernatural powers -rulers were allowed to wear this mysterious gift of the earth, and only if they left i...

Ass #8 : Diamond Cutting Diamond Cutting History: -Thousands of years ago, people considered diamond rough too sacred to cut or shape. They believed that tampering with it would destroy its supernatural powers -rulers were allowed to wear this mysterious gift of the earth, and only if they left its magic undisturbed. -Cutters in India and Europe began to process diamonds in the mid-1300s. Due to technical limitations, diamond “cutting” was mainly superficial polishing of the rough. -By the mid-1400s, people had found that diamond crystals could be easily split along certain crystal directions, parallel to the cleavage planes. This process, known as cleaving -In the 15th century, increased global exploration fueled trade between Asia, Europe, and the Americas. As a result, more rough diamonds found their way to Europe. -European cities such as Venice, Amsterdam, Antwerp, and London became diamond trading and cutting hubs, with local Jewish communities dominating the industry. -In 16th century precise diamond cutting required the development of smooth, fast, and continuous rotary motion with minimal vibration. -Cast-iron polishing wheels with continuous rotary motion greatly expanded what cutters could do with diamond rough, taking superficial polishing to genuine faceting -first was the invention of the bruting machine by Henry D. Morse and Charles M. Field in the early 1870s -Bruting, the process by which a rough diamond is shaped to its basic face-up outline to prepare it for faceting, is an essential step in cutting. -This changed in 1900, with the invention of the motorized diamond saw by E. Loesser, a Belgian immigrant to the United States. The motorized saw used a circular blade coated with diamond powder, which made the process fast and accurate. New Era: -The end of the 1930s, Belgian & Dutch Jews had established diamond cutting factories in what is now Israel. -discoveries in Africa in the late 19th century marked the birth of the modern diamond industry. The supply of and demand for gem diamonds broadly expanded. -reawakening of the Indian diamond cutting industry occurred at the end of the 19th and beginning of the 20th centuries -The 20th century(1980s) saw three significant advancements in diamond cutting technology: rough mapping, computerized planning, and laser processing making diamond cutting more efficient and more profitable. Evolution of Diamond Cuts: -Since few examples of the early cuts still exist, experts rely on images and descriptions of jewelry in old paintings, catalogs, and diaries to understand what they looked like. -The point cut was the earliest diamond cut. It appeared in the late 13th century and was common into the 15th century., his cut closely followed the rough’s octahedral shape. -Table Cut: the mid- to late 1400s, cutters found that the tips of stones tended to chip or break easily. They began to grind the tip off so it was flat, polished square facet that resembled a tabletop, known as the table cut. -Often cutters also removed the lower point of the crystal to make a smaller square facet (the culet).The result was that the table cut looked like a square within a square when viewed from above. appealed to Renaissance Europe’s interest in classical proportions. -Both the point cut and table cut followed the nature octahedral form of the a diamond -Rose Cut: rose cut appeared in the early 16th century and was popular until the 19th century, -The rose cut has a flat bottom and triangular facets that come to a point at the top. The rose cut’s facets produce considerable brilliance, this cut made efficient use of flat rough or chips created by cleaving. -Briolette :developed variations on the rose cut: instead of a flat bottom, the double rose has faceted peaks on both sides. The briolette resembles an elongated double rose. Evolution of Cuts Continued: - Single Cut: mid-1600s, cutters introduced the single cut—or eight cut—based on the shape of octahedral rough, it had more potential for brilliance than the table cut because it had more facets: a table, eight crown facets, eight pavilion facets, and sometimes a culet. -The single cut served as the basis for the full-cut modern brilliant. Today the faceting of small diamonds often stops at the single cut. -The Mazarin cut, also called the double cut, was a cushion cut with a total of 34 facets and was created mid 17th century at the request of Cardinal Jules Mazarin. - mid- 16th century to the 1700's the experimentations evolved into the modern brilliant cut. -Old Mine Cut: The old mine cut is a cushion shape with a high crown, deep pavilion, and large culet and was the most popular cut of the 18th century -this cut has the same number of facets—58—as the modern brilliant, but its pavilion is deeper, so it has less brilliance and fire. - The old European cut has features similar to the old mine cut, but it has a circular girdle, and was often cut a cushion, the square outline was easier to shape and followed the outline of the octahedral crystal closely. This was before the bruting machine’s invention later in the 19th century. -Marquise Cut: the feminine form of the French word marquis—a title of royal rank between a duke and an earl. the gem and jewelry trade, “marquise” describes an outline shape: an elongated oval with pointed ends to resemble a womens lips Contemporary Cuts : - the modern brilliant cut was formed in the early 1900s, with intricate proportions showcase a diamond’s brilliance and fire with dazzling effectiveness. -the round brilliant has dominated the market and been the most influential. - In the late 1800's Henry Morse discovered a range of angles and proportions that produced the effect he wanted with the aid of the bruting machine allowing them to cut round shapes. - He began advertising these diamonds in 1870. -In 1919 diamond cutter and engineer Marcel Tolkowsky published round brilliant cut proportions, many of which were similar to Morse’s. d -Prior to 1900's weight retention was a priority in cutting diamonds higher weight retention helped compensate for the higher weight loss associated with new sets of angles and proportions that cutters began using. A very thin girdle edge became popular in this time period. - By the 1950's the modern brilliant cut we are familiar with was the dominant cut used, this cut included lengthening the lower half facets, increasing girdle thickness to avoid chipping, and increasing the table size (under Tolkowsky’s influence). -In the 1990s, many manufacturers and retailers promoted “ideal cut” round brilliants, which were marketed as having the best proportions for maximum brilliance and fire. Fancy Brilliant Cuts: -Fancy-shape diamonds were cut beginning in the 16th century and success of the round brilliant inspired cutters to apply the modern brilliant style to fancy shapes. -New shapes made more efficient use of oddly shaped and off-color rough -aAdvances in technology and engineering, cutting fancy-shape brilliants became much easier, making these diamonds more affordable. - Leon Finker developed a triangular brilliant in the early 1960s and named it the Trillion. It became so popular that people began referring to any triangular brilliant as a “trillion.” -In the late 1970s, Henry Grossbard patented a rectangular brilliant-cut diamond naming it the radiant. - A square or rectangular brilliant called the princess cut appeared soon after the radiant. Cut Trends: - popularity of different shapes and cut styles changes as trends come and go like most luxury goods, for example popularity of different shapes and cut styles changes as trends come and go. - Some cuts are popular in certain areas or cultures. The best example is polki diamonds, which are favored in India and widely used in Indian-style jewelry. The Cutting Process and Technology : -Diamond cutting has consisted of four main stages: planning, rough dividing, outline or profile shaping, and polishing. Planning: Planning is the most crucial stage of diamond cutting—whether a diamond manufacturing business is profitable depends on it. - planners study the diamond rough in detail, including crystal directions, surface features, and inclusions, then develop a cutting plan and mark the rough for further processing. -Crystal direction is extremely important for planners in determining how to divide the rough. - planners relied on loupes and microscopes aided by making a polished window to view these features - the ultimate goal of this stage is to find the best combination of weight retention, quality, and market value. -Modern technology no longer focuses much on crystal orientation, instead mapping and computer aid planning (software) - mapping diamond rough is to either submerge it in a solution with a metal frame or wrap it in a specially manufactured glass with refractive index similar to that of diamond so the machine then scans the stone in 3 dimensions - The videos and maps are then transferred to software paired with the scanning machine for further analysis. The software analyzes the scan and latest market value trends to propose multiple cutting plans. -In modern diamond cutting factories, planners evaluate or adjust the computer-proposed cutting plans based on their observations and strain in the stone which is not an automate process -Planners determine the strain by observing the stone using a polariscope and often magnification. -Companies in Israel and India are at the forefront of diamond cutting technology. Dividing Rough: -Marked rough diamonds are divided into sections before cutting occurs. The goal of this stage is to precisely execute the plan with minimal waste. -To prepare for cleaving, cutters used a sharp piece of diamond to scrape a notch—called a kerf—into the marked rough. Next, they placed a steel cleaving blade in the notch. Then they tapped the blade with a hammer, splitting the diamond cleanly in two. - However, cleaving is rare today due to modern splitting techniques. Sawing: - Early sawing techniques made more efficient use of the rough and increased weight retention. The invention of the rotary saw dramatically increased the efficiency of the process. - a laser beam cuts the diamond with heat. For this reason, a laser can split the rough along any direction. -Compared to blade sawing, a laser beam follows planning marks on the rough more precisely because it is controlled by computer software and can split the rough along any direction. -Laser sawing also retains more weight than blade sawing -Advanced Laser Cutting uses green laser technology, a more advanced laser sawing system—using a laser guided by a water jet—was created for better weight retention and less damage. -The inventor took advantage of the principle of total internal reflection to keep the beam in focus within the water jet. Bruting: - Following sawing, Bruting shapes the diamond rough to the projected profile of the finished stone,Large numbers of rough diamonds are still bruted by forcing one diamond against another to shape a rounded girdle. - Cutters use two dops, one for the rough diamond and one for the diamond used for bruting. A dop is a holder that secures a diamond during processing. Bruting Continued....... - Bruting was fully automated in the late 1980s. Two stones can be bruted simultaneously, with each shaping the other, or stones can be shaped by diamond-studded lathe. -Automated bruting has virtually eliminated bearding, minute or minor fractures running perpendicular to a bruted girdle. Fancy Shape Bruting: - fancy-shape bruting is difficult, so laser bruting was introduced in 1992. The laser beam can create precise and symmetrical outlines much more easily than traditional bruting. -technique has been especially helpful for shaping fancy and asymmetrical outlines. -Today, many diamond cutting factories primarily use lasers to brute fancy-shape diamonds. Round-shape diamonds are still bruted mostly by automated machines. Coning: - the next to follow bruting is coning, a process of forming the pavilion angle and is most commonly done on round-shape stones as well as stones with strain - Coning is a completely automated process. The diamond is dopped and placed horizontally so it can spin against a vertical shaping wheel where consistent pressure is used along with water to keep it cool - Coning can be done on a polishing scaife as well. A scaife is a rapidly spinning horizontal wheel coated with diamond powder that is used to polish diamond rough,The longer a diamond is polished on a scaife, the higher the risk of damage Polishing: - Polishing, the last phase of the cutting process, gives a diamond its finished dimensions. Faceting and polishing occur at the same time - The polisher uses a scaife, usually made of cast iron and coated with diamond powder, to polish the rough - Prepare for polishing, the dop holding the diamond is fixed firmly into a device called a tang, which rests on a steady surface near the scaife. -The tang allows a polisher to adjust and maintain a diamond’s angle in relation to the scaife. -a diamond must be polished perpendicular to its graining rather than parallel to it. -Blocking is a crucial step in polishing. The cutter polishes the first 17 or 18 facets: the table and sometimes the culet, plus eight crown main and eight pavilion main facets. -Blocking must be done carefully because it establishes the diamond’s basic symmetry. -The last step, brillianteering, consists of polishing the remaining facets—for standard brilliant cuts they are the star and upper and lower half facets. -Polishing is the most manual labor-intensive stage in the cutting process. Quality Control: - Manufacturers must meet the standards of modern consumers more educated about diamonds than in years past which making quality control crucial - Quality control specialists also determine whether the stones match the standards requested by specific buyers.