It seems like it's a pretty small crystal (largest dimension is about the width of 4 human hairs - if I understand correctly). I'm curious as to how they actually found it...
Basically, they took chunks of what they already knew was a very old (~3.6 billion years old) rock, ground them up, separated out the zircon grains, and dated many (100's to 1000's) of individual zircon grains.
It would probably have been found by someone looking for the ages of rocks. In which case: probably sifted out of buckets of earth, looking for signs of extreme age. Seems like it's from a known-interesting area, which would attract that kind of crowd.
