"To skin a flint" is an old English idiom meaning

> To be extremely mean or miserly with money — someone who will go to absurd lengths to avoid spending anything

Example

> He’s so cheap, he’d skin a flint to save a penny


It comes from the image of trying to get even the tiniest bit (like a spark) out of a piece of flint — suggesting someone who squeezes value out of even the smallest thing

Is it used nowadays?

Rarely used today in everyday conversation, especially in American English

It’s considered oldfashioned, but still understood, especially in British English or literature

Modern equivalents

Pennypincher

Cheapskate

Tightwad (US)

Stingy

Frugal to a fault