An Alethiometer is a small, gold-coloured, compass-like device that has a single, simple, use: to tell the truth. It can reveal any truth and can answer any question when properly manipulated; the alethiometer harnesses Dust to produce its knowledge. Its name is Aletheia ”truth” + -ometer”measuring device”. The last known owner of such a device was Lyra Silvertongue.
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