The couple, who spent a lifetime building up the collection, made it a condition of their will that nothing be revealed about them or their reasons for building up the collection.

BBC: Antique finds go under the hammer

Britny Alvarado, a 15-year-old eleventh grader in Connecticut, is building up her ringtone collection.

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Although building up an atlas collection is much more expensive, he adds that it the cost of buying beautiful, historically important maps is not necessarily eye watering.

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