D
- Debase
- To lower the silver/gold value of the coin by altering its purity, but with the same face value as the pure coin. This often happens during periods of high inflation.
- Denticles
- Small toothlike projecting points on the inside edge of coins.
- Designer
- Artist or creator of a coin's design.
- Device
- Pattern or emblem used in the design of a coin.
- Die
- Metal piece engraved with the design used for stamping the coin.
- Die Clash
- Caused when a coin planchet fails to be placed between two dies during the minting process, causing the dies to smash together. The design of one or both may impress into the opposite die, causing a "shadow" of the design to appear on subsequent coins minted with the damaged dies. The impact of the two dies may also result in die cracks or defects.
- Die Crack
- Fine raised line on a coin that was caused by a crack in the die.
- Die Defect
- Imperfection of various sorts caused by a damaged die. May refer to a crack or clash or a chip out of the die, etc. A defect from a chipped die is called a cud.
- Die State
- A variation in appearance to a coin struck by a single die, resulting from wear or alteration of the die. For example, the presence or absence of die cracks may signal a specific die state.
- Die Variety
- Minor variation in a die, including repunched mintmarks, doubling, or deliberate minor changes to the die design.
- Dime
- United States $0.10 coin. Derived from the old English "Tithe", meaning "1 of 10" (The Dime is one tenth of a dollar.) While the term is American in origin, Canadians often use the term as well.
- Dipped, Dipping
- Chemical cleaning of a coin with a diluted acid.
- Double Eagle
- United States gold $20 coin. Struck from 1850 to 1933.
- Double strike
- A coin where a die is struck, bounced, then struck again, offset from first strike (used for ancient coins where hubs were not used).
- Doubled Die
- Die that received two misaligned impressions from a hub; more commonly, a coin struck by such a die.
- Doubloon
- Popular name of a Spanish gold coin originally valued at 4 dollars. The formal term was "2 escudos".
- Dump
- Centre of the holey dollar with a value of fifteen pence.
Read more about this topic: Glossary Of Numismatics