Types of clays and their temperatures

There are several types of clays, and everything depends on the amount of minerals each contains; therefore, depending on the proportion, they are classified as low, medium, and high temperature.

Below, I explain each of them:

Pottery, 850º-1050º C, Low Temperature, 5% reduction

Its main or only component is clay. It has low mechanical strength (i.e., it's brittle) and is colored because clay has a high iron content.

The burning is done in an open oven (wood-fired ovens) or with a simple composition.

Majolica, terracotta and clay are examples.

Earthenware, 1100º-1150º C, Medium Temperature, 10% reduction

Blanca: A fine, porous, white paste. It can also be colored with metal oxides. It has medium strength and is used to make decorative objects for the home, such as flowerpots and lamps.

Semi-vitreous: More absorbent, more resistant than white earthenware, used for making tableware.

It is manufactured in ceramic fiber ovens (gas) and electric ovens.

Stoneware and Fine Stoneware, 1200º-1300ºC, High Temperature, 15% reduction

Opaque and impermeable paste, of variable color, with a high clay content. They are impact-resistant. They are manufactured from thick, finely detailed pieces such as floor tiles and sinks to thinner ones such as tableware.

We work in all processes: mold, casting, pressing and turning.

Porcelain, 1300º-1450º C, 16% reduction (depending on the process)

The clay it's made of is kaolin. They are white, vitrified, and absorb almost no water. They don't require glazing.

Bone china: It is translucent and so resistant that it can be thin.

It is used for very fine tableware and lamps.

Refractories, from 1400 to 1800 º C

Heat and high temperature resistance. They have a high silica content and are hard. This is what ceramic kiln bricks are made of.