Introduction owl window, Jimmy's Pub, Redwing, Minnesota, by Kjerland Studios, Northfield.
Owl Window, Jimmy's Pub, Redwing, Minnesota,
by Kjerland Studios, Northfield, Minnesota, 1994

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I believe this art historical collection of stained glass sites is unique on the web. It certainly took a lot of finding. I put the core of this site together for an Elderhöstel, which I taught in Fall 1999, for the Northfield Arts Guild, but have now expanded and made it a permanent complement to my Art History Browser.

Before you explore, there are some things to bear in mind.

  • Most printed publications about stained glass are strongly biassed in favour of Early Medieval glass. The nineteenth-century Clayton and Bell window to the right, for example, would be deplored as being too realistic, too dark, and covered with too much paint. This is extraordinary. The history of stained glass is the history of ingenious attempts to EXPAND the range of possibilities. Check out the historical technique links below to see this for yourself.
   detail of Clayton and Bell Window, Church of the Incarnation,
Manhattan, and link to tour

How they did it

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The big challenge with stained glass is to find a way to get the brightest range of colours with the fewest pieces. You can just mosaic the pieces together, but that will produce an awful lot of black leading. Below, I have presented the techniques in chronological order of development, so that you can see the range of possibilities widening.

The Origin Myth
This site explains that glass has been made for something approaching 3500 years. Then it gives the origin myth, as passed down by Pliny. That's where I've started you.
What is Glass?
Lovely illustrated explanation of the timeline, chemistry and techniques of glass making, including some information on natural glass. From the Canadian Museum of Civilization. Supplement the images of the cylinder-blown glass process with these excellent ones from Infovitrail.com. —CURRENTLY UNAVAILABLE 6th June 2007
Cast Flat Glass
- Good pics from Infovitrail.com of a plain glass window from Roman Britain that illustrates the opacity problem mentioned in the links above. If you read French, click on the link above the pics for more history.
Pot-Metal Glass
This is your basic stained glass of a single colour. This very clear explanation comes from Glasshütte Lamberts, Germany, a modern firm of glass makers. Lamberts calls this glass "genuine antique glass" but its technical name is "pot-metal glass".
Flashed Glass
Lamberts explains again. Flashed glass is a layer of coloured glass on clear (in the Middle Ages); or it can consist of coloured glass "sandwiched" around clear. Variations in the thickness can produce pleasing modulations in colour which were exploited for highlights in the Middle Ages, or they can produce light coloured streaks ("streaky glass"). As a modern supplier, Lamberts' flashed and streaky glasses are multicoloured and densely streaked, which would not have been the case in earlier periods.
Black Enamel Paint
eagle feeding young,
Chartres cathedral, detail of window, and link to site l'Autoroute du Vitrail
Black enamel was made from ground glass plus iron filings. It was used to create the details on the earliest stained glass. On the right, you can see it used to make feathers on an eagle. It could be applied thick and black, or as a thin grey or grey-brown wash. How sad that the wonderfully fluid thirteenth-century Chartres example has disappeared. The link above now shows you one of the earliest figurative windows in existence.
Grisaille
Grisaille is the use of that same black enamel to create patterns on clear glass. Grisaille was used quite widely from the beginning, and it became increasingly common until it all but replaced stained glass in what little was left of the market in the seventeenth and eighteenth centuries. The link above will show you a modern example and one from c.1612.
Silver Stain—SUBSTITUTE LINK 7th June 2007
Silver stain was fired onto clear glass to produce a translucent yellow - or any colour between murky brown and deep amber. It was discovered around the beginning of the fourteenth century, apparently in France, and was used sparingly at first, and then very creatively to produce local contrasts on coloured glass. The new link above shows and discusses several examples. Be sure to check out this lovely early German example. Also take a look at Edward Burne-Jones' use of silver stain in a nineteenth century window - it produced the clear yellow flowers on the seraph's robe, as well as his medium brown hair. Burne-Jones, of course, was a purist - but just admire the multicoloured effects in this fifteenth century window from Fairford, Glos (UK)!
Etched and Silver Stained Flashed Glass
What a pity the Hermitage has removed its picture of the angel with the red and yellow plaid robe. But they've replaced it with this piece by the same early German glassmaker combining the same techniques. You know what flashed glass is (see above), and you know what silver stain is too (also above). Next, they expanded the range by etching areas of colour from the flashed glass so that the resultant clear spots could be silver stained - as in the red and yellow standard showing the knight's arms in this link. Check it out!
French Etched and Silver Stained Flashed Glass—NEW LINK 7th June 2007
A nice (if slow) example from the V and A of a 16th century French window showing very clearly the clear slashes etched into the red flashed glass and the lovely yellow silver-stained embroideries and hair. No blurs, no distance. Definitely check it out - and while you're there, take a look at the two other windows.
Sepia Enamel
Sepia enamel was developed somewhat later than black enamel, but like it, it was fired onto the glass. It was made from iron sulphate, sienna, and copper filings, and it produced a range of brownish colours. The superb link above shows a "Medievalizing" Burne-Jones window from Lanercost Priory, Cumbria, painted entirely in sepia, silver stain and black enamel.
Painted Glass
Meanwhile, a new development began in Italy, which would change the nature of stained glass for ever. From the fourteenth century, translucent oil paint was painted onto stained glass to enrich the range and quality of colours. In 1370, Cennino Cennini wrote this about making stained glass: After the [black] enamel has been applied and fired, colour is applied in oil paint which is just left to dry. The link above will take you to a glorious sixteenth century example of blue and purple oil paint on coloured glass by Guiglielmo de Marcillat.
More on Painting Glass
This link gives a little more information on the various methods of painting on glass discussed above. It begins with a description of "vinegar trace paint" and "matt paint", which seem to be the modern terms for two kinds of black enamel paint. Note the different ways they were used - you can see the scribble particularly clearly in this window from Tours.
Etched Flashed Glass with Silver Stain and Enamel Paint
Now here's a find! A modern piece using all the techniques so far! A very nice close-up showing the etched flashed green glass that made the stripey leaves, the subtle silver stain on the irises, and the coloured and black enamel paint that made the rich shadows. Take a look! Then check out some more of this artist's projects.
Etched Flashed Glass
Scroll down to panel 6 to see the clearest image of etched flashed glass you'll ever come across. This is another modern piece, so the technique is used in a prominent way that Medieval glass makers would have deplored. But I really like it.
Restoration Glass
Here is a useful bit of technical history from James Hetley and Co Ltd, which alerts us to the impact of the industrial revolution on glass making. This in turn lets us infer some context for all the handicraft-oriented technical and stylistic revivals of the nineteenth century.
Cathedral Glass
Lamberts shows you how "cathedral glass" is made. It is a form of "plate glass" (rolled, not blown), and is highly polished on one side and textured on the other.
Opalescent Glass
Opalescent glass is cloudy and marbled with colour, like an opal. It was made famous by John LaFarge and Louis Tiffany, and it became very widespread in the nineteenth century. The link above is very clear and also shows how some areas of opalescent windows were set with extra plates of clear glass to mute the colours or details.
To see the intended effect, look at this Tiffany Window. Contrast the brightness and clarity of the flowers in the foreground with the water and hills behind - that misting was achieved with extra plates of clear glass - as were the wonderfully translucent magnolia blossoms.
Tiffany's colours and copper-foil method
- Ruthann Logsdon Zaroff sets out the chemistry of the colours on the first page, and explains the copper-foil technique whose less obtrusive joint-lines replaced traditional heavy leading. Check out the title link for Opalescent glass (above), to see how how fine copper-foil joins can be, and what tiny pieces can be accommodated.
Drapery Glass
This link takes you to a single, gloriously clear image of opalescent drapery glass - the surface is wrinkled like a damp fabric. To see drapery glass in use, look at this Transfiguration Window by Tiffany. Christ's robe is made entirely of drapery glass.
Dalle de Verre—LINK UPDATED 6th June, 2007
Powell Brothers explains and illustrates Dalle de Verre glass. Be sure to visit the Private Collection page, which has very clear pictures! Dalle de verre (also called facetted glass) was invented in France at the turn of the century as a form of paving. It consists of thick slabs of roughly chipped glass which catch the light richly. These slabs are set in a sand box, and concrete is poured between them, so there is no need for leading. It is rich and effective, and remarkably cheap.
Float Glass
A nice explanation and illustration by Onehunga Glass Co. Ltd. Invented in 1952 by Sir Alastair Pilkington, it involves floating molten glass on a bed of molten metal to produce technically flawless glass - in sheets as large as 20 sq ft and one inch thick! It became commercially available in the early 1960s and is what you see in all those pure glass skyscrapers.
Float Glass Painting
The technical perfection of float glass can make it seem sterile. But it can be enlivened through the use of ceramic colours that fuse with the glass, and other enlivening effects such as sandblasting, etching and silkscreening. Here is a photographic tour of the technique as implemented for Skowmon Hastanan's work at the Early Childhood Center, Queens.
Fusing Glass
Schott claims to initiated fusing glass as an architectural medium in 1994. It can be fused onto insulating or window glass (or onto itself), to provide yet another way of avoiding leading. Click on the text links under the pictures in this site to see a range of interesting examples. —NEW LINK 2nd December, 2005
Golden Crane AwardThanks to
The Creativity Portal
for this award,
May 2002
Courtesy Page
This page contains links to interesting sites that did not fit easily into the teaching sections. I'm rather proud that professional glass suppliers, restorers and teachers are linking to me. Do pay them a visit.

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Introduction
and
Techniques
Medieval Renaissance
and
Baroque
Recent
Revivals
New
Directions