Final answer:
Paul Revere's professional life was primarily focused on his silverwork, making him one of the foremost American silversmiths of his time, before he diversified into iron and copper work post-Revolutionary War.
Step-by-step explanation:
The material that was the focus of Paul Revere's professional life as an artist and craftsman was silver. Revere was one of America's most renowned silversmiths before the Revolutionary War, producing exquisite silver items like flatware, spoons, tableware, and service ware, which he sold in his store. His craftsmanship was not solely limited to silver; after the war, he turned to other materials like iron, creating a foundry in Boston and becoming noted for mass-produced items such as church bells, copper pans, and cannons. The quality of Revere's silverwork was such that items like the silver tankard with the domed top and the monogram 'SEB' were typical of his detailed and refined workmanship.