Prophetic story during supper

While we were having dinner tonight. I was intrigued by a statement that my grandmother said. My grandmother, being old at 77, always have stories from her past that she shares to me. And I enjoy listening to those stories of how life was during World War II. It's like crossing into a timeline where my mother wasn't even born. It draws pictures from imagination of how things were. How people traveled, what customs they had, lifestyle, and how they survived during the war. It was all so amusing. I can also recall of stories that she said was handed down from generations of our family. There is a story told where her grandmother, or her grandmother's grandmother said that "things" made of steel will be seen in the sky, (airplanes) some will float on water (boats), and some stories which i can only describe as a modern submarine. Those where told decades ago when nothing of the sort existed. My grandmother would tell me these hundred of times. She does not have any mystical power or anything, but sometimes she has a knack for saying things that comes true. Anyway, during supper she goes at it again. However, this time she mentioned a rather new story laid down by ancestors, it is said that, time will come where in money as we know it will change. It will be made of leather, and that will be a sign that apocalypse is near. And then she continued, ''i don't know, maybe it will come after millions of years''