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China And Glassware

( Originally Published 1931 )



HERE are two ancient and closely allied products from which the shopper expects paradoxical virtues. Primarily associated with the dining room, they are expected both to give the appearance of fragility on the table and to demonstrate their ruggedness in the butler's pantry. Should a plate or glass be dropped in the dining room, the shopper, as hostess, would be mortified to see it bounce undamaged on the floor; but, as housewife, she wants that same plate or glass to withstand chipping or cracking in the sink.

Because of this conflict of interests there are certain points which the shopper may well bear in mind when making her selections :

a. Buy only from "open stock" patterns, so that broken or damaged pieces may be replaced in separate purchases. More will be said below about the open-stock policy.

b. In choosing glassware take special note of the contour. In tumblers and goblets the great danger of chipping lies in the rim. To minimize this danger some glasses are reėnforced by refusing and doubling the rim over; other glasses are so shaped that the top is tapered in from the larger diameter in the middle of the glass, thus protecting the delicate rim from many of the impacts which lead to chipping.

c. In china, too, the greatest danger of chipping lies in the edge of plates and cups. Some plates are reėnforced with a slight ridge under the edge and some cups are tapered at the rim; but chips will occur at these exposed places and it is well to remember that they will be particularly obvious if the decoration at the edge or rim is of a dark color; for it is the glaze which chips off and exposes the light color of the clay from which the china has been made.

CHINA

From the mud pie left by the child to bake in the sun to the gold-encrusted bone china service plate is a single line of progression in refinement of materials and processes of manufacture. One of the first things man learned to do was to form receptacles out of soft clay and harden them in the sun or in the ashes of his fire. Progress was rapid, and the Chinese of the Ming dynasty were making porcelain which is now treasured by art connoisseurs for the beauty of its texture and design. Indeed, porcelain, as distinct from earthen-ware and pottery, was introduced to Europe from China and derived its popular name from that source.

POTTERY

There is considerable confusion in the use of names in this field. Pottery is really a general term describing all articles made of clay and fired, or baked. In modern usage, however, pottery is applied to opaque wares as distinguished from the light, translucent, and more fragile porcelain which is generally described as china. At the same time china is popularly used to describe all the dishes used in serving meals (cf. the china closet), although many of those dishes are nothing but glazed earthenware.

Hard porcelain, a highly vitrified product, was first developed in China, and now is successfully made in Europe also. American porcelain is a "soft" product, only semi-vitrified and a halfway development from simple pottery. England has developed one of the finest porcelains in bone china, the chief constituent of which is bone ash.

How Good Porcelain Is Made : The basis of good porcelain is kaolin, a fine, white clay first used for this purpose in China some two thousand years ago. With this are mixed feldspar and quartz. The care used in the selection of these materials, the exactness of the proportions and the thoroughness with which the mixture is cleansed of foreign matter all make for the quality of the product.

The first steps in manufacture are thorough mixing and kneading by machine. The clay is then allowed to season, after which the kneading process is continued by hand until the mass is a smooth and putty-like strip.

The clay intended for plates and other flat pieces is thrown on a disk cut to the pattern of the ware and is pressed by hand into this mold. Then a metal rod bent to the proper shape is lowered over the disk and as the latter is revolved the rod scrapes off the surplus clay, reducing the ware to the proper thickness and fashioning it to the required form.

The preliminary step in making cups and other hollow ware is called casting. Here the kneaded clay strip is watered to the consistency of thick cream, poured into plaster molds of the size and shape desired, and left there for a few moments. This allows some of the clay to adhere to the sides of the mold; the rest is then poured off. What has remained in the mold is permitted to set, and the potter then has his rough clay shape which he smooths off on his wheel.

From the potter's wheel the shaped pieces are sent to the drying room for a few hours; then they are ready for the first firing, or baking. For porcelain this firing is done at a comparatively low temperature simply to harden the clay in its desired shape. This is known as the biscuit, a porous product similar to our flowerpots.

Now comes the highly important process of fixing the glaze which is the distinguishing mark of good ware. The piece is dipped into a tub of chemical solution the preparation of which is a carefully guarded trade secret in many potteries. The dipping must be skillfully done, as the solution must be evenly distributed without runs, waves, or other inequalities. The ware is then ready for its second firing, which is at a white heat of from 1,400° to 2,400° Fahrenheit maintained for some fifteen days. The terrific heat forces the solution through and through the ware and bakes it until the piece is thoroughly vitrified. During this process each piece is placed in a separate clay receptacle to protect it from any impurities in the flame and from scorching.

There are two kinds of glaze, underglaze and over glaze. In underglaze the decorative design is applied to the biscuit before the ware is dipped in the glaze solution. In overglaze a sizing is applied to the ware after it has been glazed. Sizing is a preparation designed to hold in place the decorative pattern during the third firing which fixes the decorations. Where a gold decoration is used, still another firing becomes necessary. Thus the distinction between underglaze and overglaze is whether the decoration is protected by the glaze or is on the surface. A ready test is to run a finger over the surface of the ware, which is smooth if underglazed.

Applying the Decoration: Color decoration is applied by the decal process, hand painting, or a combination of both. The decal process is similar to that which children use in transferring decalcomania to paper or books. Indeed, most large potteries employ girls to cut out and apply decalcomanias, which come in sheet form. Careless, slipshod work here becomes plain in the finished ware, and irregularity of line and lack of artistry in the decoration are good reasons to suspect the quality of the body of the piece. Certain potters have successfully developed a method of out-lining the design with decalcomania and filling in the color by hand. The hand-painting method is self-explanatory, its cost depending largely on the ability of the artist employed.

Gold decoration is the most expensive, with the possible exception of certain hand-painted designs. In some cases a solution containing a large percentage of gold is applied by hand and, after firing, is burnished. In the embossing process gold is applied to a raised pattern of the clay somewhat as icing is put on cake. In the etching process, gold is applied to a design which has been bitten out by acid. This is the most costly form, a wide gold band running the price of a china dinner or luncheon service up into the hundreds of dollars.

We have seen how the finest grades of hard porcelain are made and decorated, and it will be readily under-stood that one of the important items of cost is the danger that the ware will be cracked or otherwise damaged in one or another of the intensely hot firings to which the clay is subjected. In eathenware the firing is less intense, the glaze is frequently a mere coating and the product is generally heavy and completely opaque. Where the glaze cracks on earthen-ware the unvitrified body of the piece will absorb acid and grease from the foods served on it.

At the same time there has been great improvement in the manufacture of earthenware and some of the best grades are better and cheaper than the poorer grades of porcelain.

It should be noted that little true porcelain is made in our country. The usual American ware is a product which stands between true porcelain and earthenware, as it has a semi-vitrified body. It can, however, be very beautiful and is a serviceable tableware. In the main it has an overglaze finish.

European Products : The best earthenware is made in England, where the leading potters also make china. England is notable also as being the only place turning out bone china.

France produces both china and earthenware.

Holland exports earthenware of the cheaper sort.

Germany makes both china and earthenware, with a few outstanding potteries taking rank with the finest in the world.

Czechoslovakia does a big business in china and earthenware, but the product does not, in most cases, rank with the products of some other countries.

Belgium makes a comparatively small amount of china and earthenware, more of the latter than the former.

In Italy and Spain most of the exported product is "period" ware made in duplication of designs of earlier days.

The Open Stock Policy: No good housewife would consider serving a course of any meal on a miscellaneous assortment of china and glass. For this reason the breakage of even one glass or plate in a six-piece set would prevent her using that set for six persons unless she were able to return to the store and buy an exact copy of the broken piece. Hence the great importance of anticipating this need before selecting a pattern.

Where a store keeps on hand a sufficient stock of a pattern and permits purchase of single pieces at any time, the pattern is known as open stock. Conversely, patterns which can be bought only in sets are closed stock. It is therefore obvious that the wise shopper will limit her selection to open stock offerings, for the mortality of glass and china is a considerable item in the housekeeper's budget.

At the same time no store can be expected to keep in stock any one pattern in perpetuity. One New York store with long experience in the selling of china and glass has established the policy of maintaining 100 different patterns as open stock. Each year twenty of these patterns are discontinued and as many new designs are added. But the discontinuance is not abrupt; it is a process extending over five years. Careful records are kept of the names and addresses of all purchasers of each pattern and as that pattern moves toward discontinuance at the end of the fifth year, these purchasers are duly notified of the impending discontinuance and thus are given full opportunity to replace damaged pieces or even to assemble a reserve of the pieces most likely to break, before the pattern is "closed out." It is the feeling of this merchant that five years is a fair life for a set of china (or, for that matter, of glassware). Other stores may be more or less liberal. However, there is nothing to prevent a merchant from advertising a certain pattern as open stock this month and of arbitrarily closing it out next month.

Hence the wise shopper will not only buy from open stock; she will also first ascertain exactly what the store means by open stock and whether she will be notified before the pattern she selects is closed out.

Definitions and Hints in Chinaware: The 100-piece inner set is the unit or basis of porcelain and earthen-ware prices. Tableware is made up in standard sets:

Dinner 100 pieces, 52 and 43 pieces.
Luncheon 32 pieces.
Tea 25 pieces.
Breakfast 17 and 23 pieces.
After dinner coffee 17 pieces.
Bridge 4 cups and saucers. The saucers are elongated to permit a sandwich to be placed on them with-out tilting the cup.

Faience is earthenware with a white enamel coat. It is used mostly for decorative tiles.

Majolica, like faience, has a white finish and is further decorated with colored lusters. It is much in demand for vases.

Luster is a finishing process with a metallic base such as copper or silver. It is similar to glaze and is used in addition to the ordinary glaze. Formerly some glazes had a metallic base, which accounts for the luster or sheen of many old pieces. Luster is used only in soft porcelain.

The way to tell underglaze from overglaze is to run the finger over the surface of the piece. In the former case the surface will be perfectly smooth.

In overglaze the knife and fork are more apt to break the surface glaze. If the body of the piece is only semi-vitrified and therefore porous, it will absorb grease and acids from the food through the resulting cracks in the surface.

Crazing results where the body of the china expands in hot water at a different rate from glaze, causing cracks all over the surface of the piece. Here again the piece will absorb grease and acids and therefore can never be thoroughly cleansed.

Crackleware is the result of purposely inducing a crazing of the glaze because of its decorative effect for vases and porcelain ornaments.

In selecting china examine the care with which the decorations have been applied, and the evenness of the glaze. The presence of black specks is evidence that the clay is impure.

Pimples are blisters caused by improper firing in the kiln and are rightly regarded as blemishes.

Ground marks are the result of trying to eliminate ridges or pimples by grinding them off on an emery wheel. These marks, left by the wheel, are apparent when the piece is held to the light.

GLASSWARE

On the walls of ancient Egyptian tombs men are depicted blowing glass quite in the same way that the modern glass blower works. Yet science and machinery have entered the glass industry to perfect the work of the glass blower and to supplement his necessarily limited production with the mass output of cheaper grades.

Sand is the basic raw material of glass just as clay is that of poreclain; but it is not the familiar sand of river bed or seashore. It is a rocklike product of special mines, which is pulverized into a pure white powder. With this base are mixed soda ash, potash, and nitrate. Then is added either lime or lead; and so important are these constituents that glass is classified as either "lime glass" or "lead glass" according to which ingredient is used. Certain other chemicals are added in making special kinds of glassware.

The kinds and proportions of ingredients used are so important that most factories guard their formulae with the utmost care. The scales used in weighing the materials are so fixed that the workmen can see only the tips of the beams, the exact amount of each ingredient being known to only a few trusted employees.

A lime content gives strength and toughness to glass, adding greatly to the durability of the product. It is used mainly for pressed glassware.

In making lead glass pure red lead and potash are used in place of lime. These are expensive materials and therefore increase the cost of lead, over lime, glass. But the use of lead imparts qualities which are essential in making fine blown ware and cut glass. Lead glass when cut reflects light rays with great brilliancy. It is also tougher and more elastic in a molten state and can therefore be blown into thin delicate ware.

A method commonly employed to distinguish lead from lime glass is the so-called "ring test." When a piece of lead glass is tapped it gives out a beautiful, bell-like tone, while the ring of lime glass is duller. This is all very well if the two pieces of glass being compared are of the same size, thickness, and shape; otherwise the test is of little practical use. More can be told from the comparative brilliance of the lead and lime products, the lead glass having the greater clarity and sparkle.

HOW GLASS IS MADE

The raw materials are carefully weighed into an assembly box and then thoroughly mixed in a special machine. The mixture is then put into closed clay pots and placed in a furnace where the materials are melted and boiled. The furnace in a glass works is kept at a constant temperature of 2500° Fahrenheit. The reason for closing the pots is to protect the mixture from the furnace which might contain impurities that would be absorbed by the fluid and impair its crystal clearness. This cooking of the raw materials continues for twenty-four hours.

Pressed and Blown Glass : If pressed glassware is to be made the molten glass (with a lime content) is then poured into a cast-iron mold of the desired shape and is pushed or pressed into every part of the design by a form-shaped plunger. The plunger is withdrawn and a blast of cold air cools the glass just enough to "set" it. This cooling process imparts a dull, lifeless color to the surface against the mold; therefore the piece is removed and reheated in a smaller furnace known as "The Glory Hole," and the luster is restored by bringing the glass into contact with the tips of the flames. This is the first or fire polish. The glass, still hot, is then finally and permanently shaped with wooden paddles manipulated by skilled workers. It remains now merely to temper the ware in a series of leers which resemble ovens some seventy feet in length. Here the temperature is lowered over a period of twelve hours from 1200° Fahrenheit to ordinary room temperature, and the pressed glassware is then ready for the market.

If the glass is to be blown the molten mixture used is one with a lead content. (A notable exception is the case of the famous Venetian glass, where the constituent is soda-lime.) It is taken direct from the furnace pots on the end of a long tube and is immediately blown by a skilled worker into the shape of a miniature balloon. This plastic ball is rolled gently on an iron slab and, with the aid of various implements, is brought to something approximating the desired form. Still attached to the end of the blowtube, this semi shaped mass is placed in a cork lined mold and blown to the final size and shape. It is detached from the blowtube by revolving the neck over a thin, hot flame until the neck can be snapped. The rough edge which results is smoothed on a rapidly revolving stone and then, as a further precaution, its edge is often reheated until it melts into a regular, rounded form. Some blown glass is too delicate to stand the intense heat of this final treatment and in such ware the edges are smoothed by beveling and polishing on stone wheels.

It is obvious from the above descriptions that glass cannot be pressed as thinly as it can be blown; also that the risk of damage in finishing off blown glass is an important cost item in its manufacture.

Cut Glass: Fully fifty per cent of what is now on the market as "cut glass" is nothing but pressed glass which is finished and polished by hand. This is a cheaper method of manufacture and produces a poorer quality of glass with less luster than the cut glass. It can be readily identified by running the fingers over the inside of the piece in question. Pressed or molded glass always has slight ridges.

True cut glass is made only from the finest product of the furnace. The glass is blown thick to the proper shape. Then the design is outlined on the glass, after which it is cut. In making even the ordinary design from fifteen to twenty different cutting wheels are used; it is a delicate process, as too great pressure in cutting cracks the glass. Once cut, the glass is polished until it attains a high brilliancy.

The chief comparisons between real cut glass and the imitation pressed stock are:

REAL IMITATION

1. Lead product with brilliant finish. Lime product lacking luster.

2. Smooth interior finish. Ridges on inside surface.

3. Heavy. Lighter than real ware.

4. Resonant ring when tapped Lacks a noticeable ring.

5. Sharp edges. Blunt edges.

6. Rich designs. Commonplace patterns.

Etched and Embossed Glass: Glassware is etched with hydrofluoric acid, which eats into the glass not protected by beeswax. The design is cut either by machine or by hand and the ware is immersed in the acid solution ; then the wax is removed by boiling water and steam. Only a perfectly tempered glass will withstand this treatment.

To emboss glass the use of the beeswax is reversed; here the wax or other resistant is applied to the pat-tern, leaving the plain surface to be eaten away by the acid.

Colored Glass: In the last few years colored glass has become the dominant note in the market. It is commonly made by adding to the original mixture of raw materials some mineral salt which will give the desired color. Ruby, pink, and orchid are colors which are difficult, and therefore expensive, to produce successfully in glass; but there is no reason why glass of other colors should be more expensive than clear glass of the same size and design.

In certain cases color is fused into the finished glass, the result being known as art glass.

White Glass and Crystal: Originally crystal applied to "glass" cut from a pure rock crystal. The process was a difficult one and the artisans required years of experience before they became proficient. Their production was limited and expensive. Nowadays, crystal has degenerated into a trade term to distinguish white glass from the colored products.

Other Varieties : Enameled glass either is hand-painted or has printed patterns pasted on the glass; and the ware is fired so that the colors will unite with the glass.

Engraved glass is done by hand. The glass cutter guides the ware against a revolving copper disk, tracing and cutting the designs he wishes to create.

Frosted glass is made by rolling the ware in finely powdered glass while the ware is still soft.

Gilded glass is made by applying gold leaf, liquid gold, or gold powder to glass. In one method the design is first etched by means of acid and then filled with liquid gold. This is known as acid-etched and gold-encrusted glass. In glass banding the workman applies the gold with a brush while the ware revolves on a disk. Gold leaf application is an old method not much used to-day. The gold leaf, beaten out very thin, is attached to the glass by glue or wax. In all these methods the ware is again fired to unite the gold and the glass.

Iridescent glass is made by outlining the design in a silver solution. It is then fixed and electroplated in a solution of nitrate of silver.

Sand blast ware has a frosted appearance which is produced by blowing fine sand by compressed air against the portions of the glass to be decorated.

SUMMARY

1. Buy from "open stock."

2. Thick glass is very likely pressed ware; blown glass is usually thin.

3. Cut glass can be distinguished from the pressed-glass imitation by its weight, resonant tone, etc.

4. Judge cut glass by its clarity, sparkle, and "life."

5. "Crystal" in the modern trade means nothing but white glass.

6. Colored glass should be no more expensive than white glass of the same shape and design, unless the colors are ruby, pink, or orchid.

7. In selecting glass with gold decorations look to the depth and width of the gold filling. These factors control the value.

8. Inspect all purchases for bubbles and seeds. Bubbles are air pockets, and seeds are specks or other foreign mat-ter, in the glass.



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