Jag är ganska säker på att det är Trillioner av Nicholas Fisk , som verkligen är från 1970-talet.
Trillions were hard, bright, tiny things which suddenly arrived, millions and millions and millions of them, one windy day in a village called Harbourtown.
No one could explain them, much less why they had suddenly arrived. Were they a blessing, as their beauty suggested, or a deadly, inexplicable threat?