Making Beautiful Glassware More Beautiful
Reprinted from the booklet "THE ARE OF MAKING FINE GLASSWARE,"
published by the Cambridge Glass Company, Copyright 1939
Issue No. 159 - July 1986
A piece of Cambridge Crystal is a beautiful thing, just as it comes from the lehr. However, there are many pieces which are made more beautiful through etching, cutting or decorating with gold, silver or platinum.
ETCHING
Etching is of three kinds: Needle Etching, Pantograph Etching, and Deep Plate Etching.
In "needle Etching," the article to be etched is dipped into a
special wax, formulated to resist the action of the hydrofluoric acid
of the etching bath, and then placed in a machine where needle points
cut off the wax in the design to be etched.
"Pantograph Etchings" is done in much the same manner except that the needles follow a key or master pattern. Pantograph Etching can usually be recognized by its conventional lines, loops and curves. It is impossible, however, with either Needle or Pantograph Etching to achieve the beauty and delicateness of the Deep Plate method.
All etched Cambridge glass is finished with the "Deep Plate," by far the most complicated and expensive method, resulting in exquisite designs and shading impossible by any other process. But the results justify the additional cost, as you will easily see the first time you pick up a piece of Cambridge Rose Point, Elaine, Candlelight or Wildflower and examine it thoroughly.
In the Deep Plate method, the master etching is first made on a metal plate. If you were to examine one, you would instantly recognize the design executed in raised metal, just like the letters on printer's type. Because of the variation in size of different pieces, it is necessary to have a separate master plate for each size of piece - goblet, wine glass, tumbler, plate and whatever others are to be etched in this particular pattern.
This plate is first covered with a special black wax or ink and the excess then scraped off, exposing the raised portions of the metal which constitute the design, while the hollows which are not to be etched remain covered with the black wax.
A special tissue paper is then laid over the plate and firmly pressed down so that when the paper is stripped off, the wax or ink adheres to it, completely covering the paper except in the lines of the design from which all wax has previously been removed by the scraping of the metal plate. After trimming away the excess, a girl very skillfully wraps this paper around the glass to be etched. In a few moments the wax hardens and the paper is then softened with a special liquid and stripped off. This leaves the portion of the glass which is to be decorated covered with wax except where the design occurs.
Another girl now takes the goblet and with wax protects those portions of the glass which are not involved in the design, such as the inside of the goblets, the top of plates, etc.
This placing of the design on the glass is a very delicate operation and must be done with extreme accuracy. Pick up a Cambridge Etching, examine it thoroughly. You'll find it exceedingly difficult to find any break in the design to indicate where it began and where it left off.
The article is then ready for the hydrofluoric acid bath, which eats away, or etches only the exposed glass wherever it is not covered with protective wax, namely in the lines of the design from which the wax was scraped off while it lay on the original master plate.
In the Cambridge plant the greatest care possible is used in formulating the etching solution and in allowing the piece to remain in the bath just the right length of time. In consequence there is a depth, clarity and brilliance to the Cambridge etched piece which you do not find in ordinary etchings. The decorative pattern formed by the etched glass is literally alive with light reflected from a million tiny surfaces. It has a delicacy of line that catches every glint of light. In its delicacy of detail, it resembles the work of the old master etchers whose work is prized by connoisseurs of art, with a value almost above price. If you compare a Cambridge Etching beside the rather lifeless, frosted etchings found on much expensive crystal, you will be amazed at the great difference, which is plain to the most casual eye.
From the acid bath, the glass goes to the automatic washing machines, where hot water removes all wax and reclaims it for further use. The glass is again inspected, this time for acid spots, thoroughly polished with sawdust and wrapped for packing.
CUTTING
Cutting is the method of beautifying glass most used by the ancient Romans, the Venetians, and the English. It is still one of the most effective. With rapidly revolving carborundum wheels of different sizes, or copper wheels supplied with a steady stream of emery dust and oil, skilled workmen follow designs which have been place before them or previously stenciled on the glass. With their wheels they are able to cut any desired design much as an artist would draw a picture with a pencil.
When the piece comes from the cutting room, the cuttings are gray and must be polished, either by buffing wheels or by immersing in a solution of hydrofluoric acid. The acid method is most generally followed in America. The acid dissolves a portion of the surface, smoothing it out and giving a beautiful polished appearance. It is more satisfactory in many ways than the old style buffing process which, if not carefully done, causes spreading or pulling of the design and distortion of the pattern.
ROCK CRYSTAL
Repeatedly the question comes up, "Is this genuine Rock Crystal?" Strictly speaking, no glassware is rock crystal. The only rock crystal is the natural quartz as Mother Nature made it. Large pieces of quartz have been formed into cups, chalices and molds. Almost invariably these are museum pieces. So, if one desires to be absolutely correct, they are the only pieces of genuine rock crystal. However, in common usage, Rock Crystal is fine handmade glassware that has been cut and polished.
Others ask the question, "Is this Crystal or is it just Glass?" Originally, crystal referred solely to the color of glass and, regardless of its quality, crystal glass was clear glass, to differentiate it from colored glass. However, in recent years the word "crystal" has been adopted by the public to indicate any fine hand made glass in contrast to cheap, machine-made glass, regardless of color. More and more you will her the word "crystal" applied not only to clear or colorless glassware of fine, handmade quality, called "Clear Crystal," but also to the same grade of colored glassware such as "Ruby Crystal," "Moonlight Crystal, " "Amber Crystal," etc.