What is Minting?
Minting is the process of producing medals by pressing a blank metal disk using a pressing machine against a stamping steel die which is a tool that has an engraved impression on its surface. Through this process the die strikes an image or a relief on the blank, turning it into a coin or a medal.
View a video about minting medals here.
Making the Blanks
Strips of metal (brass, copper, nickel silver, silver or gold) of specified width are cut from metal sheets of specified thickness using a shear cutter. The strips are then cut using cutting dies to produce blanks. If a Proof or Brilliant finish is desired then the blank planchets are polished (by a rotating brush).
The word minting is usually exchanged with striking and stamping. The minting press utilizes very high pressure (e.g. 300 tons), to impress upon the blanks a negative motive of the die. After fixing the top and bottom dies in the minting press, blanks are fed to the press and are stamped on both sides at once. If the medal is required to have a low relief then one strike is enough, however, Proof or High Relief medals may be struck two or more times. After each strike, the medal must be heat treated to reduce its hardness.
Depending on customer requirements, different procedures are used to produce different types of medals. Minted medals can be gold plated, silver plated etc... They can be chemically treated (artificially oxidized) to give them an antique appearance, sandblasting may be required, surface polishing may be applied, even hand color-filling may be required.