PYX /piks/ n. a wooden chest historically used to store sample coins from the UK’s Royal Mint while they awaited testing for integrity

Have you ever heard of the Trial of the Pyx? I hadn’t until today. Now it’s your turn…

The Trial of the Pyx is a tradition going back to medieval times that was put in place to keep the Royal Mint honest. The way it worked (and still does, albeit with a more ceremonial than useful purpose) was that throughout the year the mint would randomly select freshly minted coins and store them in wooden trunks, called pyxes, until the trial took place.

For many years these pyxes were stored in a room at Westminster Abbey, which became known as the Pyx Chamber. The picture above shows an old pyx in this chamber.

At the actual trial, which takes place at the hall of the Worshipful Company of Goldsmiths, a jury of ASSAYERS (people who perform chemical tests on metals) is appointed to run a variety of tests to make sure the coins conform to a legal standard. To help them in their tests, a special Trial Plate is created having the precise composition expected of the coins…

Did you notice the use of the word COMMIX (to mix together) in this particular trial plate? Although its meaning is self-evident here, I don’t think I’ve ever seen this word ‘in the wild’ before.

In addition to testing the coins in public circulation, the trial is also used to test ceremonial coins known as MAUNDY money. This refers to coins that are printed and distributed as part of a religious tradition known as Royal Maundy, but I think we’ll call that one homework.