Not always the case. I've had the same thing that happened to Ken's happen to a LOT of compasses. I kill a compass in about three years that way. It can be 30 year old military surplus, and in three to four years, it will be inverted.
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-IronRaven

When a man dare not speak without malice for fear of giving insult, that is when truth starts to die. Truth is the truest freedom.