Different kinds of Clay that can be used in pottery

Clay Pottery
Pottery tends to be coarser than porcelain and can be broadly classified as earthenware or stoneware. Earthenware is usually of buff, brown or red color depending on the color of the clay used. Earthenware pottery is porous and not as strong as stoneware. Earthenware pottery made of red clay is called terracotta. If this type of clay pottery is glazed, it can be used for liquids and used in microwaves too. Stoneware is non-porous and can take different colors.
Stoneware is usually vitreous or semi-vitreous, not translucent. Clay pottery is often glazed or coated with a thin layer of glassy paint. This glaze is dusted or sprayed or brushed on to the clay pottery. A glaze seals and smoothens as well as colors the surface of the clay pottery. Compounds of aluminates, silicates, oxides and tin or lead or copper are used for glazing. Clay pottery vases, urns and chalices can be used to decorate your living space. Team up exquisitely crafted clay pottery bases with lamp shades.
Clay pottery must be used for cooking only if the coloring and glazing is made from safe materials. Beware of items that contain lead paint. Clay pottery items, if used for cooking can wear over time and become damaged. Though clay pottery items can handle very high and low temperatures, sudden temperature changes must be avoided. They must not be placed over direct heat. Do not place cold clay vessels in the oven. Soak the dishes or pots in soapy water and then scrub gently to clean them.

Red Clay Pottery
Red clay pottery exudes warmth from its earthy tones and can be used for kitchen utensils and home décor alike. You can use red clay pots for planting your seasonal herbs and indoor plants. This type of clay pottery is warm, red-brown and earthy in appearance. Clay pottery can be formed or molded into intricate patterns. Unglazed pottery pots are porous, and plant roots remain cooler and dry out more quicker than in glazed pots. Ensure good drainage with all kinds of clay pottery containers. Use clay pottery drip saucers or trays under the pots to catch escaping water. Be it the simple round pots or decorative pots and planters, red clay pottery has a timeless appeal. Pick up exquisite terracotta pottery for your home.
sources:http://www.targetwoman.com/articles/clay-pottery.html