A lot of people ask  "What is Pewter?"  It's a good question,  one of which the answer to has changed many times over the centuries.
Pewter is an alloy.....that part of the answer has not changed over the years,  but the contents of the alloy has.

An alloy is a mixture of natural elements, which permanently change the properties of those elements.  Once combined, the mixture is renamed, almost as if a new element was formed.

Examples of non-alloy metals which are natural elements:
gold
silver
tin
to name a few.
These metals are found in nature "as is" so to speak and contain no other  ingredients.  (exceptions may occur in the jewelry industry.)

Metal alloys, however, contain two or more ingredients, which after combining with each other,  form a new metal.  Often it takes on new characteristics,  such as color, density, higher or lower melting points, weight, etc.

Examples of metal alloys are:

Pewter - tin, antimony, bismuth, copper, lead
Bronze - copper and tin
Brass - copper and zinc

Pewter, depending on its use, can be made with various combinations and proportions of metal ingredients.  Over the years,  these combinations have varied greatly.
Plates and hollowware that may be used for serving food,  usually contain a mixture  without lead, due to lead's carcinogenic nature.  Antimony helps keep pewter bright and almost tarnish free.  Copper acts to soften pewter, making it more workable.
Other pewters contain bismuth, lead, copper,  etc.,  depending on the nature of how the pewter is to be used.  Properties are changed in order to give the pewtersmith better control over the end results of his or her work and to keep the metal looking nice for many years to come.  (removal of lead also helps protect the greater population from lead poisoning.)  Casting pewter may need a lower melting point or have better "flow" quality  to reach all cavities of the casting mold.
Some pewter pieces need a little extra strength, such as buttons,  in order for them to perform their intended functions.  Changes are made to suit the need.

Today's Pewter alloy is comprised mainly of tin (85 - 90 %)
In order for pewter to meet the standards of American Pewter,  it needs to contain at least 92% tin.  (Pewter used for hollowware in my work shop contains 94% tin.)

Through the centuries,  pewter has contained  metals, such as silver and lead.  Thus when you see some of the older pewters,  they are usually very dark gray with tarnishing,  and rich with a natural, and beautiful patina.  (silver and lead do tarnish easily.)  Pewter antiques are said to have a greater value in this tarnished condition, and great care should be taken not to disturb any of their natural beauty.  Modern pewters do not contain enough metals that tarnish as easily, and therefore seldom need to be polished.

Please don't hesitate to contact Paris Hill Pewter with any further discussion,  questions  or comments about pewter.        (ICQ #151579120)   

                                                                                          Steve