Angel gilding is a term of unknown origin used to describe the process of gilding glass

Glass

Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...

 or gold plating

Gold plating

Gold plating is a method of depositing a thin layer of gold onto the surface of another metal, most often copper or silver , by chemical or electrochemical plating...

 by electroless chemical deposition. Glass gilders use the term to distinguish the chemical process from gold leaf

Gold leaf

right|thumb|250px|[[Burnishing]] gold leaf with an [[agate]] stone tool, during the water gilding processGold leaf is gold that has been hammered into extremely thin sheets and is often used for gilding. Gold leaf is available in a wide variety of karats and shades...

 gilding also known as Verre églomisé

Verre églomisé

Verre églomisé, from the French term meaning glass gilded, is a process in which the back side of glass is gilded with gold or metal leaf.In one method, the metal is adhered using a gelatin adhesive, which results in a mirror-like, reflective finish in which designs are then engraved. The metal...

. Gold chloride

Chloroauric acid

Chloroauric acid is a inorganic compound with the formula HAuCl4. This pale yellow compound is a common precursor to gold in a variety of purposes. The term chloroauric acid is also sometimes used to describe other gold chlorides....

 is dissolved in water, mixed with other chemicals and poured on clean glass that has been treated with stannous chloride. The gold layer is delicate and usually translucent. To make an opaque, affordable and adherent mirror, a layer of silver is deposited over the gold.

History

Justus von Liebig

Justus von Liebig

Justus von Liebig was a German chemist who made major contributions to agricultural and biological chemistry, and worked on the organization of organic chemistry. As a professor, he devised the modern laboratory-oriented teaching method, and for such innovations, he is regarded as one of the...

, widely credited with inventing the modern process for silvering

Silvering

Silvering is the chemical process of coating glass with a reflective substance. When glass mirrors first gained widespread usage in Europe during the 16th century, most were made of an amalgam of tin and mercury, but by the 19th century mirrors were commonly made through a process by which silver...

 glass, also worked on gilding glass with gold chloride. James Pratt, a British glass worker, was the first to realize that he could make affordable gold mirrors by depositing a layer of silver on top of the gold. He was granted a British patent in 1885. Gold mirrors and gold mirrored signs were very popular in English public houses (pubs) in the late Victorian era

Victorian era

The Victorian era of British history was the period of Queen Victoria's reign from 20 June 1837 until her death on 22 January 1901. It was a long period of peace, prosperity, refined sensibilities and national self-confidence...

  and many wonderful examples of the art can be found all over Britain today. Felix Andres, a sign painter in San Francisco, introduced a process for spray gilding glass in 1923 but the fashion for elaborate detail in signs was changing to the modern neon

Neon

Neon is the chemical element that has the symbol Ne and an atomic number of 10. Although a very common element in the universe, it is rare on Earth. A colorless, inert noble gas under standard conditions, neon gives a distinct reddish-orange glow when used in either low-voltage neon glow lamps or...

 style and his business was not successful.

Stained Glass in Chicago

Angel Gilding was widely used by Chicago’s stained glass studios in the 1920s and 30’s to make a distinctive style of stained glass for Chicago’s historic bungalows. These Prairie Style windows have a clear glass background with the designs picked out in opalescent glass and double-sided gold mirror. To make the double-sided gold mirror the studios Angel Gilded large sheets of thin (1.6 mm) glass. A worker would cut two copies of the desired shape from the glass and place the pieces back to back in a single came

Came

A came is a divider bar used between small pieces of glass to make a larger glazing panel, sometimes referred to as leaded glass. This process is then referred to as "leading". Cames are mostly made of soft metals such as lead, zinc, copper or brass. They generally have an H-shaped cross section,...

. Because the pieces are gold on both sides, they catch and reflect the light whether the window is viewed from inside the house or from the street. Frank Lloyd Wright

Frank Lloyd Wright

Frank Lloyd Wright was an American architect, interior designer, writer and educator, who designed more than 1,000 structures and completed 500 works. Wright believed in designing structures which were in harmony with humanity and its environment, a philosophy he called organic architecture...

 used double-sided Angel Gilded glass in many of his windows, including the now demolished Imperial Hotel in Tokyo

Imperial Hotel, Tokyo

The Imperial Hotel, Tokyo, Japan, was created in the late 1880s at the request of the Japanese aristocracy to cater to the increasing number of western visitors to Japan. The hotel site is located just south of the Imperial Palace grounds, next to the previous location of the Palace moat...

.

Today

Today Angel Gilding is used to gild inside blown glass sculptures, repair Chicago’s stained glass bungalow windows create new glass signs and replicate and repair Victorian glass signs.