The stallholder who sold me this solder specializes in goods bought at auction. It was part of a job lot of smoke damaged goods from an electricals shop, the result of a fire caused by faulty wiring.
Antimony shares with bismuth, gallium and water the unusual property of expanding slightly when it freezes. This makes it ideal for casting, where it pushes its way tightly into the mold to reproduce fine detail. As a result, antimony is included in the alloys used to make typefaces for printing presses: 60% lead, 30% antimony and 10% tin is a traditional recipe.