The Story of our Pewter ~
Pewter is a metal alloy, traditionally between 90 and 99 percent tin, with the remainder consisting of copper and antimony acting as hardeners. Lower grades of pewter may contain as much as 60% lead, giving them a bluish tint. In the late 1950’s the Federal Trade Commission and the American Pewter Guild worked together define pewter as 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." This definition serves to promote a standard of quality and to protect consumers from deception in the marketplace.
Lead has been used in pewter alloys because it is easy to cast and less expensive than tin. However, lead is a known toxin that accumulates in the body causing numerous physical ailments. In recent decades, focus on this problem has resulted in the elimination of lead in gasoline and paint. Now there is increasing concern and discussion about lead content in metal alloys used in items that come in contact with people, particularly children. This has led to the recall of millions of metal jewelry items that were manufactured overseas.
All Pewter is Not the Same
TierraCast uses an alloy called Britannia, composed of 92% tin, 7.5 % antimony and .5% copper. Tin is refined from ore that contains other metals, including lead. A chemical process is used to remove the lead, but trace amounts still remain. Although all pewter contains trace amounts of lead, the term "lead free pewter" is used to describe pewter that meets the stringent FDA standard of less than .05% (or 500 parts per million) lead content in pewter in contact with food. The voluntarily adoption of this "standard" appears to have been to identify alloys that would meet the Food and Drug Administration' s regulation that limited lead in pewter in contact with food. That regulation, FDA 2009 Food Code 4-101.13 (B), states: "Pewter alloys containing lead in excess of 0.05% may not be used as a Food-Contact Surface." Unfortunately, many jewelry components are made of metal containing substantial and sometimes alarming amounts of lead.
Tests that we have run on other cast jewelry components yield lead contents as noted in the chart below.
TierraCast takes the issues concerning lead very seriously and buys only pewter that is routinely tested to comply with stringent FDA limits. Most of our pewter tests at less than 40 ppm and we refuse metal at or above 100ppm. This way, we protect our clients, ourselves and our environment from exposure to lead.
Yours in jewelry making adventure,