The probability that two snow flakes would be exactly alike, in molecular structure and in appearance, is very minute. That’s because 1) not all water molecules are alike and 2) snow flakes are affected by atmospheric conditions–they are sensitive to temperature and change their shape and design as they fall. To have two snow flakes with the same history of development would be very unlikely.
If you wanted to prove otherwise–if you wanted to prove that there are two snowflakes exactly alike, it would be virtually impossible to do so. That’s because each winter there are about 1 septillion (or a trillion trillion) snow crystals that fall from the the clouds! To compare them all would take about a hundred thousand years!
Snow crystals make up snow flakes. There may be similar snow crystals–but it is highly unlikely that one would find two matching snow flakes.
Interesting! And interesting learning is forever learning!