What did Grandpa Joe take out from the ancient purse? Why?

Grandpa Joe took a silver sixpence from the purse, so that he and Charlie could get one more chance at getting a winning ticket.

The old man gave Charlie a sly grin, and then he started rummaging under his pillow with one hand; and when the hand came out again, there was an ancient leather purse clutched in the fingers. Under cover of the bedclothes, the old man opened the purse and tipped it upside down. Out fell a single silver sixpence. ‘It’s my secret hoard,’ he whispered. The others don’t know I’ve got it. And now, you and I are going to have one more fling at finding that last ticket. How about it, eh? But you’ll have to help me.’