Glazed or unglazed?
Some times the artist wants to show off the nice color or texture of the clay and choice do not glaze it, this is especially true for techniques where colored clays make nice designs. Unglazed ceramics is better used only for dry food unless it is treated for use with liquids and protected from dust. Again, be assured of it by the potter him or herself.
Glazing ceramics has not only the objective of making it beautiful, but also to make the piece impervious to water and to make it easier to clean.
Now, there are quite a variety of glazes: matt, semi matt, velvet matt, glossy, crystal glazes, metal-saturated and so on. Some of these are not commended for tableware.
If you like mat glazes choice velvet or semi mat, better than dry mats. Mat glazes might be susceptible of scratching when used with fork and knives: this is an ugly feature especially for the white colored ones where grey lines show off the knife work. Also, spoon, forks and knives are noisy on matt glazes and for this reason they are not the usual choice at restaurants and hotels. It is difficult to imagine a formal dinner where a silence pause is only broken by the scratching of the cutlery on the plates.
Obviously, this is no problem in countries where chopsticks are used, yet still matt glazes are not considered the best choice for tableware submitted to intense use, as they are not completely impervious to water and difficult to clean.
At home, there is no reason why you should not enjoy mat glazed ware, salad bowls, plates or chargers as table centers, yet it is wise to provide melamine, plastic or wood spoons and/or forks for self helping.
A crystal is an accumulation of oxides making concentric, usually geometrical, more or less irregular motives. There are oxides very prone to form crystals: zinc oxide, magnesium and others as cobalt for blues, manganese for lilacs, nickel for brown or blues and so on depending on the composition of the glaze and firing schedule. I am sorry to tell you that these are not commended for tableware. This is because especially the extreme well-formed and big crystals may detach from the glaze and protrude as needles.
Crackling being an aesthetic enhancement is also not commended for tableware for the simple reason they let liquids to permeate into the body of the piece and allow accumulation of dirt in between crevices. This problem is minimized when the piece has been fired to a high temperature (220~˚F or 1250˚C up) or has been especially treated. Even so, heavily crackled glazes as the one called snowflake are completely out of question.
If you are fond of crackled glazes, the first time you use a crackled piece, boil it for a while with strong green tea (black tea may give a dark coloration) or disposable vegetables and wash it with a soft detergent.
But please, do not think that glossy glazes are a poor option, among them there are quite a variety: transparent, opaque, opalescent when not in the limit line with mats: mottled and so on. Some of them like oil spot or hare fur tenmoku whose physics is not completely
In the other hand, transparent glazes crystal clear or colored allow for a variety of decoration techniques enhancing the whole: under-glaze painting, carving, sgrafitto on colored slips, sprigged applications and so on.
Celina's Past Blogs:
Celina On Ceramics