The scene
Auction House · Packing tableA miniature has ended up inside one of three chests. Each chest opens with a different key: circle, square or triangle. The miniature is in the triangle chest; the camera shows that, but did not capture a face.
The keys were handed out inside wrongly labelled envelopes. The three recipients kept their envelopes and used only the key inside. Just one envelope was weighed before they were opened.
What we know for certain
One of these people stored the miniature without accomplices. There is one key of each shape and one envelope bearing each label. All three labels are false: none names its contents. There were no loans or exchanges. All weights are exact.
The three accounts
Gala Soler
Valuer«I received the envelope labelled with a square.»
Hugo Palau
Secretary«My envelope had a circle drawn on it.»
Iris Costa
Packer«I was given the triangular label.»
Examine the evidence
0 of 5 openedOpening these five clues does not cost points.
01The keys
The circular key weighs 10 grams; the square key 20; the triangular key 30. These are their only relevant characteristics in this case.
02The packaging
Each empty envelope weighs exactly 5 grams. It contains one key and nothing else.
03The surviving weighing
The envelope labelled with a circle weighed 25 grams before it was handed out. It was not opened again until it reached its recipient.
04The allocation
A photograph confirms the allocation: Gala received the square label; Hugo the circular label; Iris the triangular label.
05The chosen chest
The recording shows the miniature going into the chest that opens only with the triangular key. No lock was forced.