The first thing to do when discussing antique ‘costume’ jewellery is to define what is meant by the term. The term was coined in the 1920s and originally referred to jewellery that was designed to go with a particular outfit, particularly couturier- designed clothing, hence, jewellery accompanying a costume. Then the definition of costume jewellery began to change, becoming ‘jewellery made with cheap materials’, ‘jewellery made to look as if it is expensive’, ‘jewellery made from non-precious gemstones’, ‘jewelry that is not expensive or is made from artificial jewels’ or ‘jewellery made with inexpensive materials or imitation gems’. Basically, costume jewellery is not meant to be expensive, and so is made from less expensive materials, silver rather than gold, for instance and imitation gems or non-precious gems. However, it does not mean that it is cheap to make, nor badly designed.
The use of inexpensive materials to make jewellery started well before the 1920s and was not always done to match a new outfit or the current fashion. In a lot of cases, jewellery using non-precious stones was made because of the rarity of more expensive precious stones. If it wasn’t possible to obtain diamonds or rubies, then substitutes had to be used. Glass was the most commonly used substitute for gemstones, from as far back as the ancient Egyptian era. Glass could be moulded easily, engraved as an intaglio, and dyed to resemble most gemstones. Foils could be placed at the back of stones. Even pearls were duplicated using glass beads covered with coloured paint and ground fish scales.
Using glass to replicate gemstones continued well after the Egyptian period, through the Roman Empire and into the Middle Ages. A glass industry began in Venice after about 450AD, and was to become centred around the Island of Murano after 1291. They specialised in glass beads, and, in the 15th century, cristallo, a very clear glass like quartz called ‘soda glass’, as well as lattimo, ‘milk glass’ which replicated enamelled porcelain, and millefiori glass made from coloured canes of glass embedded in clear glass. It is not known, however, cristallo was used to make imitation gems for jewellery but it was certainly the clearest glass available at the time.
In the 16th century, glass jewels, which were usually foiled, were created for the elite to wear in portraits and to embellish their dresses, particularly to meet the need for pearls that decorated so many gowns. Travelling, too, was dangerous and so glass copies of fine jewellery were made to avoid theft. By the 18th century, though, the increased availability of wax candles which led to more evening activities, better diamond cutting coupled with the discovery of Brazil and its gem deposits, and the development of a wealthy middle class all combined to create a requirement to demonstrate one’s wealth and social standing by expensive finery and jewellery. Glass paste jewellery became popular again, not because diamonds and other gems became scarce but because they were so expensive. It became very important that the glass stones really did look real. Jewellers met the need for realistic glass jewellery that sparkled under candlelight.
Up until the 17th century, glass was molded and lacked the sparkle of real gemstones. Rock crystals, which had a higher dispersion, was often used to duplicate gems in preference to glass because it could be polished and faceted to some extent. However, in 1675, flint glass which has a high lead content, was developed in the UK by George Ravenscroft. It had high dispersion and higher refractive index than molded glass or rock crystal. Then, in 1724, French jewel designer Georges Frédéric Strass came up with ‘paste’, a leaded glass that he cut and polished with metal powder until it shone like a diamond. Named white ‘diamante’ or ‘strass’, the stones became very popular in Parisian high society.
Creating imitations of diamonds and other precious gem developed into an thriving industry, particularly in France. In 1767, 314 French jewellers formed a corporation of ‘joailliers-faussetiers’ (fake jewellers). Paste stones, in a range of different colours, remained popular and acceptable in the 18th and 19th centuries. In 1840, a process to permanently foil pastes was discovered.
Many 18th century paste stones had a small spot of black paint on the culet. It was said to be used to simulate the dark spot seen on the culet on a brilliant cut diamond.
Other types of glass gems were made. In 1763, James Tassie, a Scottish gem engraver, developed vitreous glass panels which were used for cameos and intaglios. A merchant in England developed opaline paste, which was a milky paste set over rose coloured foil, imitating opals. Vauxhall glass was made by a mirror glassworks in Vauxhall, London. This was glass that was faceted, then applied to a metal background which was then pained black. It was used to imitate jet. Another glass imitant of jet was French jet, which was hard and glittery, and colder to the touch than jet.
Toward the end of the 19th century, Daniel Swarovski, an Austrian jeweler, introduced cut-glass crystals as diamond imitations. These were made of high-lead-content glass and had a permanent foil backing. Eventually they were used to imitate coloured gems as well, including rubies, sapphires, and emeralds. In 1892, Swarovski patented a mechanical glass cutter so his crystals could be mass-produced to meet the high demand.
In 1895, Swarovski moved his family business, originally located in Bohemia, to Austria near the Rhine River. Rock crystals from the area around the Rhine were known as rhinestones but the term became associated gradually with glass or paste stones.