Art. VII. Porcelain and Porcelain Clays.
Art. VII. Porcelain and Porcelain Clays.
Through the kind offices of a friend, we have been furnished, from one of the great porcelain manufactories in the vicinity of Paris, with a series of specimens, to illustrate the elegant art of fabricating porcelain. The specimens begin with the raw materials, and exhibit them in all their principal stages of advancement up to the perfect vessel, including the materials for the glazing, and the colours for the painting, and the application of both. At the request of the manufacturer, through whose liberality we were indulged with this gratification, we transmitted to Paris various specimens of American porcelain clays. This gentleman has caused them to be subjected to trials in the porcelain furnaces, and he finds that some of them are equal to the French porcelain clays, and some superior. As our specimens were all labelled with the names of the places, in this country, from which they were obtained, we hope soon to learn where to look for porcelain clays, equal or superior to those celebrated ones from which the superb French porcelain is manufactured.
As this subject is one of much practical importance to the rising arts of this country, and as much interest has been excited in Paris concerning our porcelain clays, we should feel greatly obliged by the transmission to us of any specimens of American porcelain clays, with memoranda of the place, the quantity, the depth at which obtained, the difficulty of obtaining, and, generally, all the peculiar circumstances. We will take care that their value shall be ascertained, if they appear promising, and a proper return shall be made to the proprietor.
To those of our readers who may not be familiar with this subject, we would however take the liberty to remark, that porcelain clays generally arise from the decomposition of granite, and particularly of that kind which is denominated graphic granite, and which abounds with feldspar. It is, therefore, in the primitive countries that we are chiefly to expect them—such as New-England, and part of the high country of the middle and southern states.
It should be observed, that if a clay, otherwise apparently good, burns red, it contains iron, and is unfit for porcelain; although it may serve well enough for more common and coarse earthen ware.