This guide explains how to unlock the Jeweler’s Safe to get the Jewelled Mask.
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Getting the Jeweler’s Safe Combination
To unlock the Jeweler’s Safe to get the Jewelled Mask take out the jeweler. Take Lyegrove’s Letter on the left desk and read it by opening your journal:
The numbers at the start of the paragraphs are the number combination needed to unlock the Jeweler’s Safe:
Opening the Jeweler’s Safe
Go to the painting on the wall and find the switch and enter the number combination: