Ken Libbrecht, author of Ken Libbrecht's Field Guide to Snowflakes, cites credible evidence for the existence of giant snowflakes, six inches across and larger:
Snow crystals, despite their legendary diversity, come in a relatively small number of general shapes, including prisms, columns, stars, cups, plates, bullets and needles. Technically, the big crystals that Dr. Libbrecht observed in Canada are known as dendrites, from the Greek word for tree, because their arms are quite elaborate, like branches thick with leaves or flower stems rich in petals. Dendrites are the largest snow crystals.Scientists have found that dendrites have a tendency to join together faster than their simpler relatives. Their complicated arms, it appears, more easily form bonds. "As the branches interlock," said Dr. Petersen of the University of Alabama, "you get these huge aggregates."
Scientists have also found that particularly large dendrites, like the ones Dr. Libbrecht observed, can become the "seeds" or "nuclei" from which big flakes grow.
(Thanks, Rose!)
