How to solve the coin puzzle in Another Code: Recollection

So, you’ve navigated the treacherous library in Another Code: Recollection and the second ANOTHER key is in your reach. However, the room it’s in has no entryways, and there’s a pile of coins nearby. How do you solve the coin puzzle?

If you investigate the table in the center of the area, you’ll find a note from Frannie that appears to be an outline of the puzzle. But while it contains some useful information, it is missing key information.

D mentions something about invisible ink that can be revealed by exposing it to fire. There’s a candle on the table, so first you need to light it. Then, take the paper and move it until the flame of the candle is beneath one of the coin slots in the middle of the page. You’ll hear a sizzling sound, and symbols will appear. If you’ve already picked up the coins, prepare to be disappointed.

There’s a scale on the desk closer to the fireplace. Investigate it, then investigate the right weight to pick up five coins, each depicting a phase of the moon. You’ll notice that the symbols on the paper are not moon phases. They’re the symbol for the zodiac Libra at various angles. So, there’s more work to do.

To solve this puzzle, you need to place a coin on the scale. The weight will shift, but more importantly, the symbol at the top of the scale will rotate to a given angle. This tells you what coin corresponds to what alignment of the symbol. Weigh one, then take note of what coin is matched to what symbol. Then go to the coin slots above the fireplace. You need to drop the correct moon phase coin into the slot marked on Frannie’s note.

It’s a bit difficult to put into words, so I’m going to leave you with some pictures. Note that, having only played through the game once, I can’t guarantee the coin order is going to be the same for you. It might be randomized, but it should give you an idea of what to do.

Once the coins are placed, the fireplace will open up and let you into the secret study.