There are currently 52 names in this directory beginning with the letter M.
Mail Bid Sale
A type of auction where bids are sent to the auctioneer via the mail. Modern Mail Bid Sales are conducted using email or a web-based form on the auction company’s website. See also auction.
major variety
A coin that is widely recognized as having a major difference from other coins of the same date, design, type, and mint.
manganese
A non-precious dark stainless metal that is not found on its own but with other metals. It has been used in alloys to strike coins, such as U.S. $1 coins, since 2000. Sometimes written using its chemical symbol of Mn.
Manila
A city in the Philippines once home to the only branch of the U.S. Mint outside the continental United States. The original mint was operated by the U.S. Mint from 1920-1946 with interruptions from World War II while the Philippines was a United States territory. The Manila Mint struck coins only used in the Philippines. Some coins struck in Manila have an "M" mintmark. Philippines coins that bear an "S" mintmark were struck in San Francisco.
Maria Theresa Thaler
The name given to any silver coin that was used in world trade, primarily in the eastern Mediterranean, since 1741. The trade coin's size and weight were standardized in 1951. It was named after Empress Maria Theresa, ruler of the territories of central Europe from 1745 until her death in 1780. Maria Theresa thaler coins struck after 1780 were dated 1780 in her memory.
market grade
The grade at which most reputable dealers and auction houses would offer an uncertified coin.
Matte Proof
A proof coin produced by the U.S. Mint mainly from 1907 to 1916 which has sandblasted or acid-pickled surfaces.
Maundy money
Maundy money, or the Queen’s Maundy money, is a symbolic handout to poor elderly recipients who served the sovereign of England. Modern Maundy money are non-circulating legal tender silver coins that are given with a small amount of circulating money instead of gifts of clothing and food. The ceremony derives from an instruction of Jesus at the Last Supper that his followers should love one another. Traditions, such as washing of the feet (mandatum) and other gifts, have evolved to a symbolic handout of money.
Medal
A coin-like object produced to commemorate an event or person. A medal is not legal tender and has no face value struck on it.
medal alignment
Medals are generally struck with the coinage dies facing the same direction during striking. This is the opposite of coin alignment. See also medal orientation.
medal orientation
When a coin is struck and the orientation of the obverse and reverse dies is in the same direction, it is said that they are in medal orientation. Coins struck like this can be flipped over top-to-bottom and the design will appear "upside down." See also coin orientation.
medal press
A high-pressure coining press acquired by the U.S. Mint in the 1850s to strike medals and other special issues.
Metal stress lines
Radial lines, sometimes visible, caused by metal flowing outward from the center of the planchet during the minting process. See also flow lines or cartwheel.
micro-printing
Very small printing used during the currency making process to help prevent counterfeiting.
Military Payment Certificates
A form of currency that was used to pay military personnel in foreign countries or be used in on-base or military-controlled stores.
milled dollar
A silver coin struck in and for commerce in the Spanish colonies of the Western Hemisphere. See also reales.
minor coin
Used to describe a coin that weighs less than a crown and is smaller and whose value is less than a crown. This definition applies to coins made of any coining material except gold.
minor variety
A coin that has a minor difference from other coins of the same design, type, date, and mint.
mint error
A coin that that is flawed as a result of a mistake that occurred during its production at the United States Mint. See also error.
Mint Set toning
Term referring to toning acquired by coins after years of storage in the original holders as packaged by the mint.
Mint State
Similar to uncirculated, it is a term that refers to a coin that shows no sign of circulation or wear.
mintmark
A letter or other marking on a coin’s surface to identify the mint at which the coin was struck.
misaligned dies
A striking error caused by one or both dies not set properly in the coining machine or worked loose during striking.
mishandled proof
A proof coin that somehow escaped into circulation or was otherwise significantly abused.
missing clad layer
A type of error that occurs when part of the metal of a clad coin separates from the planchet.
Modern Commemorative
Term used to describe a commemorative coin produced since commemorative programs were restarted in 1982. See also commemorative.
Modern Era
Term used to describe coins produced since 1965. At this time, all circulating coins were made using base medals except for the Kennedy half-dollar from 1965-1969 when the amount of silver was reduced to 40-percent.
mottled toning
Uneven toning, usually characterized by splotchy areas of drab colors. See also toning.
motto
A word, sentence or phrase inscribed on a coin to express a guiding national principle. For example, E Pluribus Unum (Out of Many, One) that is inscribed on all U.S. circulating coins.
mule
A mule is a type of mint error that occurs when a coin is struck with two dies that were not intended to be used together. See also error.
multiple-struck
A type of mint error when the coin was struck more than once. A multiple-struck coin can show the design as it is struck in multiple places.