Franklin Peale Peale designed a new machine to cut planchets, or blanks, from metal strips. This machine remained in use, almost unmodified, until 1902. Another of the steam-powered machines Peale had installed on his return was a milling machine, which was used to "upset" the coin—to form a rim around it. A Contamin portrait lathe was imported from France and installed at the Philadelphia Mint in 1837. Prior to this time, all coin dies for American coins had to be made individually, by hand at Philadelphia. Once the lathe was installed, they could be reproduced mechanically by the pantograph-like device. The first
Metal clay leaving the pure sintered metal. Shrinkage of between 8% and 30% occurs (depending on the product used). Alloys such as bronze, sterling silver, and steel also are available. Metal clay first came out in Japan in 1990 to allow craft jewelry makers to make sophisticated looking jewelry without the years of study needed to make fine jewelry. Fine silver metal clay results in objects containing 99.9% pure silver, which is suitable for enameling. Lump metal clay is sold in sealed packets to keep it moist and workable. The silver versions are also available as a softer paste in a pre-filled