Definition
To coin money is the sovereign power to create lawful metallic currency: to shape a metal of intrinsic value into a standardized form and impress upon it a government-sanctioned denomination, thereby authorizing it as legal tender and facilitating its circulation in commerce. The phrase is a term of constitutional art in American law, drawn directly from Article I, Section 8 of the U.S. Constitution, which grants Congress the power to "coin Money, regulate the Value thereof, and of foreign Coin."
The power encompasses three interlocking functions: selecting and acquiring the metallic substance, determining the weight and fineness of each coin, and fixing the nominal value stamped upon it. Together these functions establish public confidence in the currency and create a stable medium of exchange.
Equally significant is what the clause withholds. Article I, Section 10 explicitly denies states the power to coin money, making the coinage power exclusively federal. The clause also operates in tandem with the prohibition on bills of credit and the requirement that states make only gold and silver coin a tender in payment of debts — provisions that historically framed a unified constitutional monetary settlement.
Common Language
Modern common usage (Wiktionary): "To coin" means to make coins by stamping metal, or more broadly, to invent or create something new (as in "to coin a phrase").
Historical common usage (Webster's 1913): "To coin" — to make or fabricate; specifically, to make (as money) by stamping metal; to convert a mass of metal into money by stamping it with an official impress.
The gap between ordinary and constitutional meaning is narrow but important. Common usage treats coining as any act of stamping metal into coin shape. The legal meaning is narrower and more structural: it is an exclusively sovereign act involving not just physical manufacture but the official determination of value and the grant of legal-tender status. A private mint that stamps metal into coin-shaped discs does not "coin money" in the constitutional sense; it potentially commits a federal crime.
Common Confusion
COIN MONEY is sometimes conflated with the broader power to regulate currency or issue paper money. The constitutional text separates these functions. The coinage clause speaks specifically to metal and stamping; the power to issue paper currency (Federal Reserve notes, treasury notes) derives from different constitutional provisions, including the Necessary and Proper Clause, and was the subject of sustained historical controversy. Researchers treating "coinage power" as synonymous with "monetary power" generally will miss this distinction and the body of historical authority built around it.
Why It Matters in Research
This term matters primarily as constitutional language rather than as a recurring term of common-law doctrine. Several navigational points are critical:
The phrase appears in federal constitutional litigation, not in ordinary private-law disputes. Researchers encountering it in case law are almost always in the domain of federal monetary regulation, legal-tender challenges, or criminal counterfeiting statutes.
Historical sources, including Bouvier, anchor their definitions in currency stability and metallic value. That framing reflects the 19th-century gold-and-silver monetary framework. Researchers working with pre-1933 materials will find a world in which the intrinsic metallic content of coin was legally and practically significant; post-1933 sources reflect the shift to fiat currency and will treat the clause differently.
The exclusivity of the federal coinage power has direct consequences for state-law research. Any state monetary instrument, scrip, or local currency scheme will run into Article I, Section 10 analysis. Researchers investigating alternative currency proposals, cryptocurrency regulation debates, or community currency schemes should treat the coinage clause as a threshold constitutional question.
Counterfeiting law (18 U.S.C. § 485 et seq.) is the most frequent modern context in which the coinage power generates litigation. The constitutional scope of what Congress may protect as "coin" informs what conduct falls within the federal counterfeiting statutes.
Historical Dictionary Support
Bouvier's single entry on this term is terse but precise. It defines the act as molding a metallic substance of intrinsic value into form and stamping on it a legal value, with the purpose of encouraging free circulation and ensuring currency stability. The citation to 2 Duvall (Ky.) 29 grounds the definition in antebellum Kentucky case law interpreting the constitutional clause.
Bouvier's emphasis on intrinsic value is historically characteristic. Through most of the 19th century, the constitutional understanding was that coin derived its legitimacy in part from the actual value of the metal — that the stamp confirmed and represented something real. This contrasts sharply with modern monetary theory and practice, in which a coin's stamped value bears no necessary relationship to its metallic content. Researchers should treat Bouvier's definition as accurate for its era and as a baseline for understanding originalist arguments about the coinage clause, but should not import the intrinsic-value framework into modern regulatory or criminal contexts without qualification.
No other historical dictionaries were available for cross-comparison for this entry. The absence of broader historical dictionary coverage is itself a research signal: this is a term whose legal significance is largely constitutional and statutory rather than common-law, and it generates less treatment in the practitioner-oriented dictionaries that dominated the 19th-century tradition.
Encyclopedia Cross-Reference
The Law Mind Criminal Law Encyclopedia: Money Laundering (18 USC 1956-1957) — relevant for the intersection of currency crimes and federal monetary regulation.
The Law Mind Business Organizations & Corporate Law Encyclopedia: Banking — Bank Secrecy Act and Anti-Money Laundering (AML) — relevant for the federal regulatory framework surrounding monetary instruments.