CHAPTER II.
CLASSIFICATION.
Tabulated View.--Brongniart’s Division: Its Objections.--Classification adopted.--Leading Features and Advantages.--Distinctions between Different Bodies and Different Glazes.
In order to avoid repetitions and explanations, and for the sake of lucidity, tabulated views of the different branches of ceramics are here presented. The first is least detailed, but gives the salient points of a systematic arrangement.
{ Unglazed Common brick. Earthen-ware. { _Soft_ { Lustrous Greek pottery. POTTERY { { Glazed Some ancient and most modern faience. { { Enamelled Robbia ware. { { _Hard_ { Stone-ware. { Fire-brick.
{ _Soft_ { Naturally soft English porcelain. { { Artificially soft { French porcelain, _pate tendre_, PORCELAIN { { such as old Sèvres. { { { China. { _Hard_ { Dresden. { Sèvres.
The following is more full, and is to be ascribed to M. Brongniart:
FIRST CLASS, SOFT-PASTE.
_1st Order._ Baked clay without glaze.
_2d Order._ Lustred wares with silico-alkaline glaze.
_3d Order._ Glazed pottery with plumbiferous glaze.
_4th Order._ Enamelled pottery, in the enamel of which tin is used.
SECOND CLASS, HARD-PASTE (OPAQUE).
_5th Order._ Fine faience, uncolored paste with plumbiferous glaze.
_6th Order._ Stone-ware without glaze, or with salt or plumbiferous glaze.
THIRD CLASS, HARD-PASTE (TRANSLUCENT).
_7th Order._ Hard porcelain, paste and glaze both felspathic.
_8th Order._ English natural soft-paste porcelain--paste, argillaceous kaolin, pegmatite, phosphate of lime, etc.; glaze, boracic.
_9th Order._ French artificial soft-paste porcelain--paste, a frit, marly alkaline; glaze, alkaline containing lead, alkali, and silica.
If these tables be studied carefully, it will be found that in arranging the nine orders, a gradual ascent is made from the humblest ware--baked clay left unglazed--to the finest of artificial compounds. Its only objection--and it is one very likely to confuse an inexperienced student of the art--is, that, under the head of hard-paste pottery, are classed the soft-paste porcelains of England and France. The question is, also, very likely to suggest itself, why the distinction should be drawn between the soft-pastes of England and France, and the one called natural, the other artificial. The reason is that the paste of England is naturally soft, while that of France is made soft by the chemical action of certain of its ingredients. The classification has, on the other hand, the advantage of being in general use. Terms are employed in its construction which have a peculiar but well understood significance; and even in its errors there is a modicum of truth. Thus, although the artificial porcelain of France is invariably called _pate tendre_, or soft porcelain, it is not improperly classed under translucent hard-pastes. The error is in the distinctive name rather than in the classification. There is, in reality, very little difference in hardness between the hard-paste and the soft-paste; and although the glaze of the latter is not so hard as the body, the appellation soft-paste has been adjudged a misnomer. The question then came to be whether it might not be better to retain the old terms, with an explanation of their technical meaning, than to supplant them with something new. The latter course has been adopted, upon the ground of obviating meaningless and misleading distinctions. Both simplicity and a clear understanding of one of the most important practical divisions of our subject point toward a revision of the old system of grouping. Pottery and porcelain differ in one essential respect, and their varieties can also be classed according to the leading features of their composition, manufacture, or appearance. These differences have been taken as the basis of the following classification, against which, at least, none of the objections to that of M. Brongniart can be brought. It has been prepared by a distinguished French artist of the present time, and is offered in the hope that it may be intelligible, although it is not claimed to be either perfectly exact or altogether complete.
All wares are divisible into two great classes, viz., transparent porcelain and opaque earthen-ware.
PORCELAIN may be natural or artificial.
I. Natural porcelain is made from kaolinic clay. It may have--
1. A pure felspathic glaze, such as porcelain of China, Japan, Limoges, Sèvres, Dresden, Berlin; or,
2. No glaze, such as the biscuit porcelain of China or France.
II. Artificial porcelain may be made from alkaline clay, calcareous clay, or felspathic clay.
1. Alkaline clay may have an alkaline glaze, either colorless or colored, or may be biscuit.
_a._ Alkaline glaze, colorless--Persia, China, St. Cloud, Limoges, Sèvres, Tournay.
_b._ Alkaline glaze, colored--Persia, China, Limoges, Deck.
_c._ Biscuit--Old Sèvres statuettes.
2. Calcareous clay has a colorless boracic glaze, as in the case of the English china of Minton, Copeland, and Worcester.
3. Felspathic clay is exemplified in the parian of Copeland, Minton, and Worcester.
EARTHEN-WARE is of two kinds--that showing a non-vitrified fracture, and that showing a vitrified fracture.
I. EARTHEN-WARE with non-vitrified fracture may have either a transparent glaze or an opaque enamel.
1. Transparent glaze may be plumbiferous or alkaline, and in either case colorless or colored.
_a._ Plumbiferous.
Glaze, colorless--Faience d’Oiron or Henri Deux ware, Wedgwood, Meakin, Creil, Montereau.
Glaze, colored--Palissy, Nuremberg, Minton’s majolica.
_b._ Alkaline.
Glaze, colorless--Persian faience, Chinese and Japanese faience; Deck, of Paris.
Glaze, colored--Haviland or Limoges faience.
2. Opaque enamel is stanniferous, and may be either colorless or colored.
Stanniferous, colorless--Della Robbia, Rouen, Moustiers, Delft, Nevers.
Stanniferous, colored--Colinot, Parville, Longwy.
II. Earthen-ware with vitrified fracture may be either glazed or in biscuit. Of the former, the _Grès_ of Germany, Beauvais, and Doulton may be taken as examples.
For convenience of reference, the same classification may be given in tabulated form:
CLASSIFICATION OF ALL KINDS OF WARE.
{China, Japan, {Glaze of { Dresden, Berlin, {_Natural_ Kaolinic { felspath, { Sèvres, Limoges. { paste { pure { { { {Biscuit {Biscuit porcelain { { of Limoges { { and China. { { {Persia, China, TRANSLUCENT{ { St. Cloud, Tournay PORCELAIN. { {Alkaline {Glaze alkaline, { Sèvres, Haviland. { { paste { colorless { { { { { {Glaze alkaline, colored Persia, China, Deck, { { { Haviland. { { { { { {Biscuit Old Sèvres statuettes. { { {_Artificial_{Calcareous Glaze boracic, color English china, { paste Minton, Worcester, { Copeland. { {Felspathic Parian Copeland, Worcester, { paste Minton.
{Glaze, {Faience Henri II., {Plumbiferous{ colorless.{ Wedgwood, Meakin, { glaze { { Creil, Montereau. { { { {Glaze, {Palissy, Nuremberg, {_Earthen body {Transparent{ { colored {Minton’s majolica. { with a { glaze. { { non-vitrified{ {Alkaline {Glaze, {Faience of Persia, { break_ { { glaze { colorless.{ China, and { { { { Japan; Deck. { { { { { { {Limoges faience { { { { of Haviland, { { {Glaze, { Bracquemond, { { { colored { and Chaplet. { { OPAQUE { { {Delia Robbia, EARTHEN { {Opaque {Stanniferous {Colorless { Rovigo, Fontana, BODY. { { enamel { { Rouen, Moustiers, { { { Nevers, Delft, TERRES. { { { Ulysses de Blois, { { { St. Clement. { { { {Colored Colinot, Parville, { Longwy. { {_Earthen body, {Biscuit Boccaro, Bizen. { with a { { vitrified { { break_ {Glaze Grès from Germany.
Under the above arrangement, it will be observed that the distinction between hard and soft porcelain and pottery is done away with. The first is divided into natural and artificial, the kaolinic paste being the only one coming under the former head, and the “soft-pastes” of both England and France coming under the latter. The subdivisions are made according to the glaze employed. The division of pottery into two classes, according to the nature of the body as revealed by fracture, is the most lucid and comprehensive. The subdivisions, as in the case of porcelain, are made according to the enamel or glaze applied to the ware. It is presumed that any one can distinguish between transparent and opaque wares, and thus tell porcelain from pottery, and similarly, tell whether the fracture of a broken specimen is vitrified or otherwise, and thus distinguish stone-ware, or _grès_, from ordinary earthen-ware.
In the matter of glazes, it requires a great deal of skill and long practice to tell one from another. All are transparent, with the exception of tin or stanniferous enamel. Felspathic glaze is that most readily recognized; but in the case of the others--the alkaline, plumbiferous, and boracic--they are very often only to be distinguished by their different effects upon the colors used in decoration.