Although it is commonplace today, glass has a rich history of technological and artistic development, and embodies the magical, alchemical, and intangible properties of the natural world. Transformed by fire and human intent, sand metamorphoses into infinite colors and shapes; glass is one basic material that is endlessly variable.
What is Glass?
Glass is the result of combining silica (sand) with a flux (a substance that lowers the melting temperature of the silica) and then heating it by fire. While glass was invented more than five thousand years ago, natural glasses also occur, such as volcanic glass (obsidian).
Labret (1400-1521) by MexicanThe Walters Art Museum
Labret (Lip Plug)
Obsidian. Aztec, ca. 1400–1521. Bequest of John G. Bourne, 2017, acc. no. 2009.20.249.
A labret is a kind of plug inserted through a piercing below the lower lip. In the world of the Aztecs and their contemporaries in Mexico circa 1300–1520 CE, the labret was usually a sign of status or even ethnic identity.
Labrets were often made of materials symbolizing the importance of their wearer, with the most important people wearing lip plugs of gold, rock crystal, or perhaps jade. This example is made from obsidian, a volcanic glass that was a frequently used material in Central Mexico.
As a brittle glass, obsidian is extremely difficult to work with, especially to shape it into the rounded forms shown here.
Glass has the ability to be transparent and solid, to be colorless or colorful, and to be shaped into infinite forms. The earliest glass was cast or formed by trailing threads of molten glass around a core. The invention of glass blowing in the 1st century BCE revolutionized glass making, allowing artisans and workshops to produce glass vessels at an industrial scale. Like the flask decorated with a menorah below, vessels could also be blown into molds to create duplicate objects quickly.
Menorah Flask
Mold blown glass. Byzantine, ca. 600 CE. Gift of Mr. Harvey M. Meyerhoff in memory of Lyn P. Meyerhoff, 1992, acc. no. 47.673.
Glass artists create beautiful works of art by coloring the glass, and by shaping and molding the molten material into pleasant and useful forms. Trails or strands of molten glass or other materials like gold can be added, and sometimes the smooth surface of the glass is further decorated by etching.
Vase with Snake-Thread Decoration (late 2nd-mid 3rd century CE (Roman Imperial)) by RomanThe Walters Art Museum
Vase with Snake-Thread Decoration
White, yellow, and turquoise glass. Roman, late 2nd-mid 3rd century CE. Acquired by Henry Walters, 1929, acc. no. 47.54.
This vessel is decorated with the "snake thread" technique, where trails of colorful glass are added to an opaque white vessel. This technique was invented in the 2nd century CE, with production centered around the Roman city that is now Cologne, Germany.
A tool was pressed against the colored glass trails while they were still hot, creating the rope-like pattern seen here. This vessel most likely held a precious substance like perfumed oil. Snake-thread vessels are often found in burial contexts.
Bottle with Colored Glass Trails ("Snake-Threads") (late 2nd-mid 3rd century CE (Roman Imperial)) by RomanThe Walters Art Museum
The trails could be quite elaborate and sometimes included elements of gold, as this snake-thread vessel once did. The gold decoration is unfortunately not preserved. This vessel, acc. no. 47.57, was acquired by Henry Walters in 1927.
For more on the development of snake-thread vessels, please see this article by former Hall and Krieger Fellow Dr. Nicole Berlin, which is also available on the Walters Art Museum website.
Material Masquerade
Glass Tumbler with the Monogram of William T. Walters
Glass. American or French, 19th century. Acquired by William T. Walters, after 1861, acc. no. 47.369.
Like naturally occurring rock crystal, transparent glass is clear–compare, for example, this tumbler decorated with the monogram of William T. Walters. The artful addition of colorants, whose shade and vibrancy were manipulated in the glass kiln by means of heat and oxygen, often resulted in glass that closely mimicked colorful stones. The ancient Egyptian term for glass translates as "the stone that flows."
Glass can be manipulated to create visual effects that are similar to carved stones. Compare the effect of light passing through the carved agate of the Rubens Vase, acc. no. 42.562, at left, with the way light shines through the layered and engraved glass of the vase with a carp, acc. no. 47.384, at right.
Revivalism: When Old is New Again
Mosaic Bowl (late 19th-early 20th century) by Salviati & Co.The Walters Art Museum
Mosaic Bowl
Mosaic glass. Salviati & Co. (Italian), late 19th–early 20th century. Acquired by Henry Walters, before 1931, acc. no. 47.298.
The Societa Salviati e Compagni (Salviati and Company), founded in Venice by Antonio Salviati about 1866, was noted for reproductions of ancient glass. The Walters has important holdings by Antonio Salviati and Salviati and Company in styles replicating ancient and medieval art.
This bowl is made in the mosaic glass technique, which was invented in the ancient world. Makers of mosaic glass cut thin slices from long, thin rods known as canes. The slices were placed side by side on a marble slab and heated in a furnace until they fused together.
Click here to see a Roman example of a mosaic glass plate. The ancient vessel has a more iridescent, weathered appearance than the Salviati bowl, though it also glows like stained glass when lit.
For more about the history and chemistry of Salviati revival glass, see the article "The Technical Analysis of a Glass Ewer by Salviati & Co." by objects conservator Angela Elliott and former Walters conservation scientist Jennifer Giaccai.
The Power of Light
Translucency and transparency are important qualities of glass that compare best to gemstones. Light activates and transforms the appearance of glass in a way that it does not for other materials.
Unlike most windows, which have transparent glass allowing the viewer to look through them, stained glass windows are meant to be looked at. The intricate scenes created by the artists are like paintings made of glass, which glow when lit by the sun. The glass used for stained glass windows is not only "stained"—it can also be colored, enameled, and even painted.
Stained Glass Quatrefoil Roundel with Hunting Scenes (ca. 1518 (Renaissance)) by Hans von Kulmbach Veit Hirshvogel the elderThe Walters Art Museum
Stained Glass Quatrefoil Roundel with Hunting Scenes
Stained and clear glass, paint, and metal. Designed by Hans von Kulmbach (German) and produced by the workshop of Veit Hirschvogel the elder (German), ca. 1508-1510. Museum purchase, 1951, acc. no. 46.75.
The panes of glass that make up the design of a stained glass window are individually shaped and then soldered together with heavy lead strips to be fitted into the design of the window.
Metal oxides melted into the glass produced brilliant colors, while silver salts fired on a glass surface produced a yellow color. Additional details for scenes could be etched into the glass or painted.
This roundel, with lively scenes of hunting and fishing plus a family's coat of arms, is a companion to another roundel (dated 1508), which bears the arms of the city of Nuremberg.
The two stained glass roundels are from a series commissioned to be set into windows, likely in a civic meeting chamber. The composition is based on a drawing by Hans van Kulmbach, one of the leading painters and designers of stained glass in Nuremberg.
Mosque Lamp (1867-1884) by Joseph Phillipe BrocardThe Walters Art Museum
Mosque Lamp
Enameled glass. Joseph Phillipe Brocard (French), 1867-84. Bequest of Dr. George Krotkoff, 2014, acc. no. 47.742.
Joseph Philippe Brocard (d. 1896), who created this piece, was a French glass artist, restorer, and collector of Islamic glass. He was inspired by the methods of enameling glass used in medieval Egypt.
This 19th-century lamp is based on a 14th-century eample from Mamluk Egypt (1250-1517).
The inscription running around the top of the object is from "Ayat al-Nur" (the light verse), chapter 24, verse 35 in the Qur'an: "God is the Light of the heavens and the earth. The parable of His Light is as if there was a Niche and within it a Lamp."
The inscription on the body mentions that the lamp was made for a madrasa (school) and mausoleum (tomb) and gives part of the name.
Islamic glass production reached a high point in 14th-century Egypt and Syria as the result of the intense patronage of Mamluk sultans and amirs commissioning civic-religious structures and palaces. In the 19th century, there was significant appreciation for Mamluk art in Europe and Egypt itself, which witnessed a "Mamluk Revival."
Beaker (ca. 1260 (Crusader)) by SyrianThe Walters Art Museum
Beaker
Glass with gilding and enamel. Syrian, ca. 1260. Acquired by Henry Walters, 1925, acc. no. 47.17.
This 13th century beaker is a rare example of fine enameled glass from Mamluk Syria. Produced in the Crusader period (1095-1291), it depicts a Christian monastic community. The band of Arabic at the top reads "Glory to our master, the sultan, the royal, the learned..."
Beyond Glass: Vitreous Enamel
Vitreous enamels, created by fusing powdered glass to an underlying material, often metal, are a particular strength of the Walters’ collections; the museum houses outstanding examples of various enamel techniques, from cloisonné to plique-à-jour and beyond.
One form of enameled glass, like the mosque lamp and beaker discussed above, involves applying powdered glass, mixed with a liquid binder to create paint, onto the surface of a glass vessel and then fusing the powder to the surface by heating the vessel in a kiln.
Objects decorated in cloisonné have colored-glass paste elements placed within enclosures made of metal wire. On early examples of cloisonné enamel, like the pendant below, which was once attached to a woman's headdress at the temples, the walls of the cells are visible and add details to the design.
Temple Pendant (Kolt) with Two Birds
Gold and cloisonné enamel. Ukrainian, 12th century. Acquired by Henry Walters, before 1931, acc. no. 44.297.
Over time, artisans experimented with cloisonné to produce objects where the wires were not as prominent, or even where the wires were removed prior to firing. The Ando Cloisonné Company, founded in Japan in the late 19th century, was a leading innovator in artistic enamel production.
Vase with Flowering Cherry and Birds (ca. 1910) by Ando Cloisonné CompanyThe Walters Art Museum
Vase with Flowering Cherry and Birds
Cloisonné enamel. Ando Cloisonné Company (Japan), ca. 1910. Gift of Stephen W. Fisher in memory of Kenneth Arden Willaman, 2007, acc. no. 44.708.
This large vase is decorated with two small birds perched on flowering cherry branches, a bloom that has long been significant in Japanese culture.
The cherry blossom has been widely celebrated in Japanese art, literature, and poetry, especially as a metaphor for the transience of life. The brief cherry blossom season, which lasts only a week, is celebrated every spring in Japan with cherry-blossom viewing in public parks.
The fine metal wiring along with the brilliance of the black mirrored surface makes this vase a magnificent example of the work of the Ando Cloisonné Company at about the turn of the 20th century.
Plique-à-jour enamel is stained glass in miniature. In this technique, the enamel is held in metal cells without a backing, allowing light to pass through the translucent enamel.
Art Nouveau Dish with Stem (1904-1905) by Firm of David Anderson Gustav GaudernackThe Walters Art Museum
Art Nouveau Dish with Stem
Plique-à-jour and cloisonné enamel, silver gilding. Designed by Gustave Gaudernack (Bohemian) and produced by the firm of David Anderson (Norwegian), 1904-1905. Bequest of Mrs. Jean M. Riddell, 2010, acc. no. 44.991.
This remarkable object, because of its size and complexity, is regarded as an outstanding example of Norwegian Art Nouveau enamel work. The bowl, which is executed in red and green plique-à-jour enamel, shows the leaves and flowers of the peony.
The dish is supported by two stems with leaves and blossoms of the same flower rising from an enameled base. This piece has been created in parts and then assembled.
Soon after the discovery of the chemical element uranium around the beginning of the 20th century, it was added to glass to impart a yellow-green color, as seen on this dish. A Geiger counter, which detects radiation, indicated this object was made with a radioactive colorant.
Since uranium-containing glass produces low levels of radiation, such glass art requires special storage, exhibition, and handling considerations.
A thin sheet of plastic is sufficient to block the radiation for long-term storage, and thick Plexiglass bonnets on cases protect exhibition visitors by absorbing the uranium radiation.
Glass is ubiquitous in daily life; everyone encounters glass. The materiality and fragility of glass is so internalized that it is used in many metaphors, such as a glass ceiling, glassy eyed, smooth as glass, or being on the outside looking in. This material, invented thousands of years ago, impacts our lives every day.
Case Watch
Gold, enamel, and glass. Swiss, ca. 1820–30. Gift of Liz and Peter Moser, 2006, acc. no. 58.289.
The United Nations declared 2022 to be the International Year of Glass in order to highlight the impact that glass has had on society over thousands of years in sectors ranging from optics to the arts, architecture to health care. We invite you to explore the Walters Art Museum's collections of glass, stained glass, and enamel online, as well as in our galleries, where admission is always free.
This Google Arts and Culture story was created by Lisa Anderson-Zhu, with assistance from Glenn Gates and Dylan Kinnett. Additional materials are drawn from the work of current and former curatorial staff at the Walters Art Museum.