Q: What is Ceramic (or "Ceramics")?
The Science of changing clay to pot (or other products such as electrical insulators) by the use of heat produces a ceramic. Clay can be dried and reconstituted to a plastic state ad infinitum but once subjected to a high enough temperature it undergoes a drastic chemical and mechanical change called, appropriately, "the ceramic change". It is no longer clay, but is now a hard, impervious, vitreous material that cannot be disintegrated and dispersed by water or most chemicals. This is what is known as "ceramic". In fact ceramic materials cannot be destroyed, sure the pot can be broken and even ground up but the chemical properties are forever. This is the material on which the whole pottery industry is founded and it is what we call "pottery" or "ceramic" ware.
Q: What is "Stoneware"? THE POTTER'S DICTIONARY by Frank and Janet Hamer defines stoneware as "A hard, strong and vitrified ware, usually fired above 1200 Deg. Centigrade in which the body and glaze mature at the same time to form an integrated body/glaze layer. The quality of the glaze contributes much to the establishment of this layer and it is the glaze quality which determines the colours of body and glaze....". (Christa mixes all her glazes to the highest possible standard).
This is opposed to earthenware, which is fired at much lower temperatures (up to, but often below, 1100 Deg. Centigrade) and is softer and more porous, with the glaze sitting on top of the clay body (not integrated with it) and therefore more subject to chipping of the ware and the glaze. (Cheaper "earthenware" often develops small surface cracks (crazing) and is far more likely to crack or chip in normal domestic use).
(All of Christa's products are "Stoneware" - fired to a minimum of 1350 Deg. Centigrade - using the highest quality clays and glazes).
Q: What is "Reduction Firing"?
"The action of taking oxygen away from the metal oxides in the glazes and clay during firing, causing the formation of a wider range of colours and necessitating the use of flames in the kiln".
"Reduction firing" is therefore not done in convection or electric kilns but in more sophisticated kilns fired with "flames" eg. Gas, Wood, Coal or, as in our case, Oil. The actual "firing" process also requires more stringent controls to produce a quality product.
All of Christa's products are produced by the "Reduction Firing" method at a minimum temperature of 1350 Deg. Centigrade to give a more mature look to the glaze and bring out a brilliant shine. This "firing" is controlled by her husband Peet.
Non "Reduction Fired" stoneware glazes are usually matte with a very limited range of colours.
Q: Do your glazes contain Lead? No. Christa's glazes DO NOT contain lead or any other hazardous ingredients.
Q: Are your products Oven/Microwave and Dishwasher proof? Yes they are but as with any ceramic product they can be cracked by "Thermal Shock".
This simply means that you should not place a cold dish into a hot oven or a hot dish onto a cold surface. Allow the dish to reach temperature with the oven or, in the case of a hot dish from the oven, place it on an insulated surface not, for example, on one of the cold stove plates.
| Home | Samples | About | F.A.Q | Contact | Map | Caring for |