“If the profession or career of the husband requires that his wife should go much into society on a small income, she would be perfectly justified in wearing imitations to save money… it cannot be wrong for a lady who cannot afford and has not inherited them to wear a moderate amount of paste.” Queen magazine, 1869
Paste is the name given to any cut leaded glass used in jewelry that resembles gemstones but particularly refers to high lead content glass. It is given its name ‘paste’ because it is mixed into a wet paste during manufacture. Because of the high refraction and dispersion, paste can have close to the brilliance of real gemstones. Pigments can be added to create any desired color. Paste is softer than ordinary glass. While glass is not a precious material, the level of skill that is required to work with paste has historically made it appropriate for fine-jewelry settings. Because of its softness, cutting paste is thought to be more difficult than the cutting of diamonds.
Cheaper paste pieces are pressed or made with molds whilst higher quality pieces are faceted and polished. Molded paste can be identified because the facets are rounded whilst cut glass has sharp edges. Although molded paste is easy to distinguish from real stones, cut paste stones may need a closer inspection. They can be distinguished from gemstones in the following ways: (1) Unlike real stones, paste usually has air bubbles that you can see with a loupe or microscope. (2) Paste stones feel warm to the touch. (3) When broken, paste has a conchoidal fracture, with brilliant curved surfaces particularly on the widest part. (4) Paste will not scratch ordinary glass. (5) Paste has an index of refraction of 1.50–1.80. (6) Paste has specific gravity of between 2.5 and 4.0. (7) Paste has an isotropic character, meaning it has only single refraction and no dichroism. Most natural gemstones are doubly refractive and dichroic. ‘Black dot paste’ is a hallmark of very fine quality paste, although not all high quality paste has this. This is paste which has a tiny black dot painted on the very bottom underside of the stone. It seems that it was added to mick the open ‘culet’ of early diamond cuts, which often look quite dark or black. (The culet is the bottom of the stone, which in times past were usually flat.)
Early examples of paste, with their high lead content and artistry, are considered the most desirable and collectible and have a particular luster.
Paste is also sometimes called ‘strass’ named after Georges Frédéric Stras, the 18th Century jeweler who became famous for paste jewelry when he invented his own method in 1724. It can also be called ‘diamante’. Although paste and glass jewelry had been in existence for centuries, it was Stras who became famous for this highly reflective, polished glass with a high lead content. These paste gems were coated or foiled and often tinted. Paste stones were not considered inferior to real gemstones; they were even popular with royalty and were certainly a big hit with high-society, particularly in Paris. Meanwhile, in Vienna and Bohemia, glass-makers were also experimenting with glass gems and working with jewelers to create innovative materials. However, it was an English man, George Ravenscroft (1618-1681), who filed the first patent in 1674 for a type of glass that was made with a higher lead oxide content and had a higher refractive index then any glass before. In the mid-Victorian era, Schlichtegroll was a Viennese jeweler famous for paste jewels.
During the 18th and 19th century, paste stones were cut as marquise, oval, pear and a variety of other shapes. Paste stones were used in shoe buckles, pendants, rings, bracelets, tiaras and all manner of adornments. During the Victorian era, pastes were often used in acrostic jewelry and most Victorian ladies owned at least a few pieces of paste jewelry. The use of paste was at its height before 1850 but continued on until the present day. ‘Paste’ came to be a name for any number of imitation and glass composite stones that were created in the late 19th and early 20th century. During the 20th century the idea of ‘costume jewelry’ became widespread. During the Art Deco period in the 1920s, Parisian designers such as Coco Chanel used large paste jewels to make statement pieces. These styles were very popular in Hollywood and in high society. After 1940, paste was made with a much lower lead content.
Austrian jeweler Daniel Swarovski was responsible for the the first cut-glass crystals that successfully imitated the look of diamonds and other precious gems. In 1892, Swarovski patented a mechanical glass cutter so his crystals could be mass-produced. Swarovski crystals were made of high-lead-content glass and have a permanent foil backing. In 1895, Swarovski moved his business from Bohemia to Austria near the Rhine River. This is how glass crystals became known as ‘rhinestones.’ Swarovski Glass Crystals were immensely popular during the Art Nouveau and Edwardian era but of course continue to be widely popular today.
Sources / further reading:
http://www.britannica.com/EBchecked/topic/445939/paste http://www.collectorsweekly.com/fine-jewelry/paste http://howtospendit.ft.com/womens-jewellery/2240-the-real-appeal-of-paste-jewellery http://trouvais.com/tag/antique-paste-jewelry/ http://en.wikipedia.org/wiki/Conchoidal_fracture http://en.wikipedia.org/wiki/Swarovski