Earthenware is made of clay fired at low temperatures, making it fairly fragile and quite heavy. Majolica, faience, delftware, and slipware are all varieties of earthenware.

Stoneware is made from fortified clay that is fired at high temperatures, rendering it very hard and sturdy. It is opaque, vitrified (fused like glass), and nonporous, and it's generally oven- and dishwasher-safe.

Porcelain is composed of kaolin, or china clay, and petuntse, or china stone, making it fine-grained and strong. It is fired at very high temperatures and is vitrified and nonporous.

Bone china is porcelain to which bone ash has been added, giving it greater whiteness and translucency. Fired at high temperatures, bone china is thin, lightweight, and durable.

Sterling silver pieces are made from silver with the addition of 7.5 percent of another metal, usually copper, for durability. "Sterling" should be stamped on the piece.

Silver plate has a metal-alloy base (usually nickel silver, a mix of nickel, copper, and zinc; sometimes brass) and is coated with a thin layer of 100 percent silver by the process of electroplating. (The term EPNS -- electroplate on nickel silver -- identifies the base metal.)

Gold plate is made by the same electroplating process, but the base metal (usually sterling silver, a metal alloy, or stainless steel) is coated with a thin layer of 10-karat gold.

Stainless steel is an alloy of steel, chromium, and nickel. The highest quality is 18/8; it has a steel base with 18 percent chrome for corrosion resistance and 8 percent nickel for luster.

Tablecloths are mostly of linen or cotton (jacquard and damask refer to the weave or finish), and hang down no more than 8 inches on all sides of the table.

Undercloths, toppers, and runners vary widely in size, shape, and material. Before you register, measure your dining table (include height from floor); take the numbers with you.

Napkins range in size from 6 inches square (cocktail napkins) to 20 inches square (luncheon) to 24 inches square (dinner).

Place mats range from 13-by-19 inches to 15 or 16 inches round. Choose a fabric that feels pleasant to the touch.

Glass is made from the melting together of sand, ashes, and ground limestone. Though usually translucent and colorless, glass can be tinted in its molten state with metallic oxides or pigments. Traditionally, glass was handblown by craftsmen; today it is more often pressed into molds.

Tempered glass has been treated to resist thermal or physical shock.

Crystal is simply glass with the addition of a small amount of red lead oxide, which lends brilliance and clarity.

Full-lead crystal (also known as lead crystal) is made with 24 percent red lead oxide. Full-lead crystal is often handblown, hand cut, and etched or engraved.