The court books of the manors of Healaugh and Muker in Swaledale, from the earliest in 1686 until 1712, show that some of the annual rents paid by copyhold tenants included an unfamiliar monetary denomination – a plack.
The rents were recorded in words and digits, making it clear that the value of a plack was one-sixth of a penny. But it wasn’t even a denomination of English currency. It was Scottish. And even in Scotland it was long-since obsolete. So what was going on? Read more here: Value of a plack: the curious case of Scottish money in Swaledale.