Term – A term used in numismatics to describe a specific coin or paper money item. These terms can be abbreviated or spelled out and are generally defined in a reference book. They can also be derived from the description of a coin on its original coin or in a numismatic auction sale catalog or other listing. A common example is the Sheldon grading scale developed by PCGS and NGC and others.
Census – A number of specimens known to exist of a particular coin. This information is important to collectors because it can help them determine the availability of a particular issue and its overall condition.
Counterfeit – A counterfeit coin or paper money that is made to appear authentic but lacks the genuine value and legal tender status of the item from which it was copied. These are usually made to deceive the unsuspecting public.
Clad – A United States coin containing a center core of pure copper and a layer of silver or copper nickel on both sides. These coins have been in circulation since 1965 and are commonly referred to as business strikes. They are not considered proofs which are specially made for collectors.
Frosted Devices – A term describing a crystalline appearance on the raised portions of the devices on a coin. This is often caused by rubbing.
Friedberg Numbers – A catalog number devised by Robert Friedberg and based on his book Paper Money of the United States, first published in 1953 and updated by his sons Ira and Arthur. These are widely used by numismatic reference authors and are an essential part of any numismatic library.