The Crime of Debasement, and the Punishment of Death
The United States Coinage Act stipulated that if a mint official fraudulently debased the coinage, the punishment was death. Why did "fineness"—the proportion of precious metal in an alloy—carry such grave significance?

The Penalty Was Death
The United States Coinage Act contains a chilling line. It stipulated that if a mint official committed fraud and secretly debased the coinage, the crime was punishable by death. The fledgling republic imposed the ultimate penalty for crimes related to its money. The background to this severe punishment was the nation's recent experience of witnessing the collapse of faith in money due to the Continental currency.
Value Not Discernible by Appearance
The fineness of a metal indicates the proportion of gold or silver it contains, based on weight. For example, a silver fineness of 0.925 means that 92.5 percent of the total weight is silver. The remainder is an alloy metal, such as copper.
Fineness cannot be determined by appearance or weight alone. If only the fineness is lowered while the weight remains the same, the amount of gold or silver it contains decreases. For instance, a coin weighing 27 grams with a silver fineness of 0.925 contains approximately 25.0 grams of silver. However, if the fineness is reduced to 0.500 at the same weight, it contains only 13.5 grams of silver. Checking the weight and analyzing the fineness are two completely different examinations.
Scales and the Time for Verification
More than a thousand years before the advent of coinage, value was weight itself. In Babylonia, the word "shekel" existed, but it was originally a unit of weight based on the weight of barley. When silver began to be used for weighing, people would cut off a piece of silver for each transaction and weigh it on a scale. This is known as hacksilver.
In a world where payment was by weight, the fineness had to be verified with every transaction. The time taken for this verification itself became a transaction cost.
The End of Civic Coinage
In 267 AD, the Heruli, coming from the north, sacked Athens and plundered Corinth and Sparta. The historian Dexippus is said to have led the resistance in Athens.
After the destruction, the city was reduced to a small quarter. Around this time, against a backdrop of debasement of the imperial silver coinage and rising prices, civic coinage came to an end. In the era of Emperor Gallienus and his successors, coinage was centralized in the hands of the empire, and the long-standing practice of cities striking their own coins almost completely ceased.
Confidence in currency, once lost, is difficult to regain. That is why the most severe punishment was reserved for those who betrayed that trust from within. The death penalty clause is irrefutable testimony to how seriously the young nation regarded the integrity of its currency.
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The City That Made an Emperor and Was Burned by a King
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The Journey of the Daalder, the Silver Coin from a Valley's Name
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Everything in these pieces comes from the material itself.