I still have one of those I acquired in my adult years. Every once in a while I would listen to stories broadcast from the BBC.
When I was about 12, a rich uncle gave me half a crown ( half a Dollar we called it, knowing that there were 4 Dollars to the £ Pound) , I felt like a millionaire.
As a child, I remembered "Play Doh." I didn't like playing with it; I liked eating it. It must have been "Non Toxic" 'cuz I'm still here at 70.
Kids putting steel washers into slot machines to 'buy' chewing gum, then one day, the shop owner put a sign in his window saying...... 'Assorted steel washers for sale, apply in shop.'
I don't know where the name came from but we used to call them slugs. They weren't washers because they had no holes can't even remember where they came from, look like the metal piece that got punched out of electrical outlet box.