The first European attempts to produce pottery with the look and feel of Chinese porcelain involved mixing white earthenware clays with so much glass that the products looked and felt more like glass – than clay-made objects. Given the nature of the first attempts to produce porcelain-like pottery in Europe it would seem that the model at hand (based on what materials were on hand) was the glass made opaque with tin oxide such as the later German Milchglas, “milk glass”.
That Milchglas itself did not become the European sought-after substitute for Chinese porcelain was probably due to the inherent differences between clay and glass per se. The nature of glass made it impossible to shape it by any of the means used by the potter, so, instead, a mixture of clay and ground glass was tried. Porcelain made in this way resembles that of the Chinese only superficially and is always termed “soft” or “soft-paste” porcelain, since it required a softer (i.e., lower temperature) firing and the product was softer (could be scratched with a knife).The date and place of the first attempt to make soft porcelain are debatable, but some Middle Eastern pottery of the 12th century was made from glass and glaze materials mixed with clay and is occasionally translucent.
Much the same formula was employed with a measure of success in Florence about 1575 at workshops under the patronage of Duke Francesco de’Medici. No further attempts of any kind appear to have been made until the mid 17th century, when Claude and Francois Reverend, Paris importers of Dutch pottery, were granted a monopoly of porcelain manufacture in France. It is not known whether they succeeded in making it, but it is known that by the end of the 17th century “soft porcelain” was being made in quantity by a factory at Saint-Cloud, near Paris.
Another product called “fritted porcelain” , but also referred to as artificial and soft porcelain, in the ongoing attempt by Europeans to emulate raw materials of Chinese porcelain (prior to knowing and having the Chinese kaolin-to-feldspar proportions) was made by pulverizing Chinese porcelain pieces and introducing the powder directly as a frit into “porcelain” clay and glaze recipes (using blends of known earthenware and stoneware clays).
Similarly, a ware called “cupel“, made of (usually) bone-ash porcelain crushed and melted and poured into moulds without any further to-do over mixing with crude clay before firing, as would be done with such a composition to be used as a frit (as in the case of the so-called ‘fritted’, or ‘artificial’ porcelains).
An Italian nomenclature used in English in reference to the porcelain-like wares made within a certain portion of the history of porcelain making. Toward the end of the 15th century Ming porcelain was being revealed to Italian potters, having as much influence on shapes (which became more delicate, subtle and varied) as it had on increasing the repertory of ornament. This was the beginning of the motifs called alla porcellana (meaning “in the style of porcelain“) painted in cobalt-blue on a white background, echoing the Ming pottery devices of floral motifs in chrysanthemum and peony, of sprays, tiny leaves and vines, either trailing or hanging in minute festoons from the border; and even framing subjects often connected with the life of those distant lands: junks, pagodas, silkworms, etc.
This family of porcelain wares was in the workshops of Faenza by the end of the 15th century and continued there for several decades, with variations appearing at Caffaggiolo and Montelupo in Tuscany throughout the 16th century.