A Trial plate was a piece of metal used as a standard in the

assaying An assay is an investigative (analytic) procedure in laboratory medicine, mining, pharmacology, environmental biology and molecular biology for qualitatively assessing or quantitatively measuring the presence, amount, or functional activity of a ...

of coins to determine a coin's accuracy and fineness. Plates made from various metals including

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pink ...

silver Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical ...

and

gold Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile ...

were used in events such as the

Trial of the Pyx The Trial of the Pyx () is a judicial ceremony in the United Kingdom to ensure that newly minted coins from the Royal Mint conform to their required dimensional and fineness specifications. Although coin quality is now tested throughout the year ...

as benchmarks of quality. A contender for the earliest known ingot-shaped silver trial plate that dates from 1279 and is held by the Royal Mint Museum in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...

References

Bibliography

* {{refend Numismatics Coins