Ceramics range from translucent porcelain to heavy ironstone, from English Wedgwood to French Quimper faience--and collectors need to know the differences.
Ceramics is a general term for heat-hardened clay items, Bruce E. Johnson wrote in an article in the current issue of Country Living, and he offered some definitions.
Biscuit (also bisque) is unglazed pottery or porcelain that has been fired only once.
Bone china (also china) dates back to 1749 when an English potter discovered that mixing a large quantity of bone ash with clay could create ceramic ware that looked similar to true porcelain but was heavier and less likely to shatter during firing.
By 1800, bone china (a type of porcelain) was being produced by many English firms and remains the standard for English wares made in the image of true porcelain.
China generally encompasses all true porcelain and bone-china tableware, as well as porcelain figurines, doll faces and more. If a plate is porcelain or "china," you can see the outline of your hand through it when held up to a strong light.
Chinese export porcelain. Chinese potters invented what is considered "true" porcelain in the 13th century and began exporting it soon thereafter.
Creamware, Queensware, pearlware, are cream-colored earthenwares developed during the 18th century. Josiah Wedgwood made a creamware service for Queen Charlotte in 1765, and then marketed creamware as Queensware.
Delft is soft earthenware fired at a low temperature and decorated with an opaque tin-enamel glaze and high temperature colors, often blue and green, named for the Dutch city where it was popularized in the 17th century.
Earthenware is any clay body that is porous until coated with a glaze and fired in a kiln. It is opaque, not translucent.
Faience is earthenware glazed with a tin-based slip--often decorated with hand-painted motifs.
Glaze is a liquid coating applied to ceramic ware before it is fired in the kiln.
Ironstone (sometimes Masonware) is a thick, heavy earthenware noted for its strength and white, porcelain-like appearance.
Limoges is named after the city near which some of France's finest clay deposits were found.
Lusterware, lustreware, lustre decoration refers to ceramic ware coated or embellished with a thin film of metal such as copper, gold, silver or platinum.
Majolica was inspired by Italian maiolica, a tin-glazed earthenware similar to faience. England's Victorian majolica makers fashioned everything from plates to garden ornaments.
Mochaware is earthenware, usually creamware or pearlware, with slip decoration applied in branching or swirling patterns reminiscent of mocha stone.
Porcelain refers to a vitreous ceramic made from high-quality clay such as kaolin, and powdered, fusible stone such as feldspar.
Quimper faience is decorated, tin-glazed earthenware produced in the Brittany village of Quimper since 1685.
Redware is earthenware crafted from red clay.
Slip, slip decoration, slip glaze are terms for an opaque glaze made by thinning fine clay with water until it reaches the consistency of cream.
Spongeware, sponged ware, spatterware are ceramic wares decorated by using a sea sponge, scrunched rag or the tip of a brush to apply color.
Staffordshire, a county in central England, has long been a major producer of ceramics.
Stoneware, very strong and durable, is often used for crocks and jugs. It is made from clay and powdered rock fused together to form a surface impervious to liquids.
Stoneware, salt-glazed, refers to stoneware glazed by tossing handfuls of salt into the hot kiln.
Transferware is decorated by the transfer-printing process developed in the mid-1700s to replace costly hand-painting.
Yellowstone is earthenware made from buff-colored clay.