Since the middle of the XIXth Century, dishes were made not only in pure porcelain or earthenware, but also in half porcelain or fine earthenware, hence halfway between porcelain and earthenware.
Fine earthenware is an opaque white clay paste, with a fine, dense and sonorous texture, covered with a lead glaze. It is halfway between traditional earthenware and porcelain.
The mixture of this white clay with calcined and ground flint creates a kind of fine earthenware called English earthenware or cailloutage. It was developed in England by Josiah Wedgwood in 1769. If chalk is added to the clay or sand, it becomes pipeclay.
If feldspar is added in the mixture and the lead of the glazing has largely been replaced by borax, one gets a hard and fine earthenware or fine feldsparic earthenware.
Commonly called opaque porcelain or half porcelain, it contains kaolin, a white refractory clay which cooks at a high temperature.
It is sometimes commercially known as “ironstone”. Fine earthenware is covered with a glazing (or transparent varnish) containing a certain amount of lead. Decoration can be painted on the body bisque or printed beneath the glazing. It has sometimes been laid upon the glazing. The enamel of the earthenware contains tin and is waterproof, while the glaze of the semi-porcelain contains lead - crystal clear (this is clearly visible, for example, in the photo of our service 4028 on our website). The decoration possibilities of semi-porcelain are very wide and as with porcelain, allow to create large dishes. Dishes in semi-porcelain are appreciated for their creative decorations, original shapes and solidity.
La demi-porcelaine
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