What is Pewter?
Unlike silver and gold, which are pure metals refined directly from ore deposits, pewter is an alloy (a mixture) of metals. While available in more than one alloy, pewter does have a clear definition established by the American Pewter Guild (APG), The American Society for Testing and Materials (ASTM) and the Federal Trade commission (FTC). The APG and FTC definitions mirror one another due to the fact that the two organizations worked closely together during the late 1950's to formulate a shared definition. The APG used this definition to promote a quality product and the FTC adopted the same definition to protect consumers from deception in the marketplace. In short, both the APG By-laws and the FTC define pewter, in its most basic type, as an alloy of not less than 90% tin.
The APG By-Law reads:
Section 3.2 Pewter – The term "pewter" for the purpose of the By-Laws is a metal alloy product of which the chemical composition shall be not less than 90 % Grade A Tin, with the remainder composed of metals appropriate for use in pewter."
The FTC definition restates the minimum level of tin, and goes on to define unfair or deceptive use of the term "pewter". The specific Code of >Federal Regulations (16 CFR 23.8) reads:
23.8 – Misrepresentation as to the content of pewter.
(a) It is unfair or deceptive to mark, describe, or otherwise represent all or part of an industry product as Pewter or any abbreviation if such mark or description misrepresents the product's true composition.
(b) An industry product or part thereof may be described or marked as Pewter or any abbreviation if it consists of at least 900 parts per 1000 Grade A Tin, with the remainder composed of metals appropriate for use in pewter.
The ASTM definition echoes the requirement for tin content and extends the definition as follows:
Designation: B 560-00
1.2 Pewter alloy shall be defined as having a composition within the range of 90 to 98% tin, 1 to 8% antimony, and 0.25 % copper.
Moreover, the ASTM Standard limits the maximum amount of lead to 0.05% lead (500 ppm). This is important to note that only the ASTM definition of pewter actually limits the amount of lead allowed in "pewter", as long as the tin content is at least 90%.
Looking closely at the APG and FTC definition, the single most important point made in those two definitions is:
ANY metal advertised, or sold as pewter MUST contain at least 90% tin. Those that contain less do not qualify as pewter under the Federal Trade Commission regulation; advertising as them as pewter is unfair and/or deceptive.