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The Story of St. Hermelin
St. Hermelin, established in 1964, is a Christian school. It's emblem, featuring a white Ermine, is looked upon as good luck. The Ermine is known to be a killer of snakes, the creatures that are the cause of human degradation and decadence. The joined X and P are both symbols of good, with the A and Omega standing for 'the beginning' and 'the end.'

In the courtyard of St. Hermelin is a giant stone known as the "Philemon Stone." It was excavated when the building of St. Hermelin was in progress, and was put there as it is believed to be good luck. The story is that an angle named Philemon came down and put the stone there to protect and bring luck to the school.

Additional Info from Michael Collins

Just a little detail

The "P" and "X" you refer to in the description of the St. Hermelin coat of arms are actually the Greek letters Chi and Rho. The Chi-Rho symbol is traditionally an abbreviation for "Christos", and is found on the candles used in Catholic masses, along with other things. The iconography basically points to St. Hermelin being a Catholic school.