Why Do They Call Fake Diamonds Paste?

In the context of jewelry, "paste" refers to a type of glass that simulates gemstones. Before 1940, most imitation gems were made from high-lead-content glass, which was called "paste" because its components were mixed wet to ensure uniform color. The term "paste" originated from the process of creating paste stones, where silica-based mixtures were combined with other elements to create colors. Paste stones, also known as paste gems or "Strass" (named after Georges Frédéric Strass, the French jeweler who popularized paste jewelry in 1724), are made of high-lead-content glass that is hand-cut to mimic the shape and color of diamonds and other gemstones. They are then polished to achieve a gem-like luster. The high lead oxide content in paste stones increases their refractive index and dispersion, making them more brilliant and capable of being polished to a higher degree than other imitation gemstones. Paste stones are also called "rhinestones" or "crystal stones."

 

In the 18th century, paste jewelry gained significant popularity in France. Jewelry designer Georges Frédéric Strass used paste stones to create fine-quality jewelry and was appointed "Jeweler to the King" by Louis XV of France. Paste jewelry quickly became fashionable, with its appeal lying in its nearly indistinguishable resemblance to genuine gemstones. In fact, in most cases, paste stones appeared even more sparkling than real diamonds. Paste stones were often more labor-intensive to craft than gemstone jewelry, as the paste glass had to be expertly hand-cut and polished. This craftsmanship made paste jewelry highly desirable, with many in Parisian high society considering it superior to real gemstone jewelry.

 

Paste stones were a common feature of antique jewelry. In such cases, rhinestones can be valuable historical artifacts in their own right. The first crystalline artificial diamond simulants were synthetic white sapphires (Al₂O₃, pure corundum) and spinels (MgO·Al₂O₃, pure magnesium aluminum oxide). Both have been synthesized in large quantities since the early 20th century through the Verneuil or flame-fusion process, though spinel did not gain widespread use until the 1920s.

 

In the Georgian era, paste jewelry was not merely seen as a substitute for gemstone jewelry but was valued for its own sake. Georgian-era women wore paste jewelry not to deceive others but to own unique pieces with artistic value comparable to that of gemstone jewelry. In those days, the technology for cutting and polishing diamonds was limited. Diamonds had to be shaped around their natural form, meaning they were mostly oval or oblong. Glass, being softer, could be cut and polished into any shape. Paste stones could be designed to fit tightly together in settings with minimal visible metal between the stones, allowing for more creative designs than genuine gemstone jewelry. Paste stones typically had a black dot painted on the center of the back to simulate a culet (the tip at the bottom of a gemstone). They were backed with clear or hand-tinted foil to create colored stones. Paste stones were produced in hues not found in nature.

 

The term "paste" in this context is a synonym for glass when referring to gem materials. Glass has been used as a gemstone imitation since ancient times because it is transparent, can be colored in various ways, and resembles many types of gemstones when polished. The first paste "forgeries" are believed to have appeared in ancient Greek society, though glassmaking had existed for a long time before then. Archaeological findings and collections spanning over 2,000 years include paste imitations, initially as cabochons and beads, and later as faceted stones. In 1674, English glassmaker George Ravenscroft patented a new glass with a higher lead oxide content, which had a higher refractive index (RI) than previous glass. It was a brilliant glass with high dispersion.

In the 18th century, paste stones were cutting-edge and used to experiment with known forms of jewelry. The softness of paste allowed it to be cut and shaped into a wide variety of forms and sizes, with small, nearly invisible settings that were difficult to achieve with real gems. Paste stones were used in various jewelry pieces, from elaborate necklaces to smaller items like buckles and shirt buttons. Paste jewelry was popular throughout the Georgian era and continued to be in vogue during the Victorian era. Many tasteful ladies would almost certainly have a paste jewelry set in their collection. Its popularity peaked in the Edwardian and Art Deco periods until around 1930. Parisian couture designers like Coco Chanel and Elsa Schiaparelli created modern costume jewelry by reinterpreting paste jewelry with contemporary techniques, catering to their Hollywood clientele.

 

Today, we often associate "paste" with fraudulent or imitation jewelry. However, in the history of jewelry, paste was once an art. Paste jewelry was not merely a substitute for gemstone jewelry but was valued for its unique artistic and decorative qualities. In summary, fake diamonds are called "paste" because they are made of a special type of glass that imitates the appearance of diamonds. This glass, rich in lead oxide, was mixed in a paste-like consistency during production. Paste jewelry gained prominence in the 18th century, particularly in France, and has since become a significant part of jewelry history. Below is a table contrasting paste and natural diamonds:

 

It should be noted that modern cubic zirconia and moissanite are also common diamond simulants. Cubic zirconia is a synthetic crystal with high refractive index and dispersion, offering good brilliance and fire. Moissanite, a lab-grown gemstone, has a refractive index and dispersion close to that of diamonds, making it difficult to distinguish from genuine diamonds with the naked eye. However, these simulants differ from paste stones in terms of composition and production methods. Paste stones are made of high-lead glass, while cubic zirconia and moissanite are synthetic crystals. Despite being imitations, they each have unique characteristics and appeal.