No two snowflakes are alike?

[tonychanyt]

Preachers are fond of saying, "No two snowflakes are alike." The statement is not quite true.

At this microscopic level, it's extremely unlikely to find identical snowflakes. In this sense, The statement is true.

What about checking them with our naked eyes?

ThoughtCo:

Since a group of snowflakes falling at the same time form under similar conditions, there's a decent chance if you look at enough snowflakes, two or more will look the same to the naked eye.

Simple, small snow crystals can be identical when we look at them. So while it's technically true that no two snowflakes are molecularly identical (just as no two of anything are identical at the molecular level), the common preaching point oversimplifies and misrepresents the observable reality. Snowflakes forming under similar conditions can and do look identical to human observers.

 

[Fervent]

...I don't think people are taking the analogy all that seriously. It's more important that the people understand the underlying point than that it map perfectly to observations. It's generally true, and true enough that the statement is not obtrusive.