Most likely, yes. The science behind snowflake formation is remarkably complex. Scientists are uncertain as to why ice crystals take different shapes at different temperatures, and the influence of humidity is also a grey area. It is believed, however, that the old saying ‘no two snowflakes are alike’ is true for fully formed snowflakes. It is estimated that there are 1018 water molecules in a snowflake, and these can arrange themselves in an almost infinite number of ways. Nobody can say for certain that there are no matching pairs, but with odds like that it is probably a safe bet.