Tarzu searches for traps on the tiny golden chest, but finding none he starts to open it...
Luckily for his quick reflexes, he avoids a smaller dart that is shot from within the chest the moment he opens it. The dart appeared to be coated in some sort of substance, but it clatters noisily on the floor...thankfully away from being hit.
As Tarzu looked around the area for more traps, he founds, straight in front of the secret panel, a second loose stone that had apparently already been triggered (by Coralie the first time). He connects it to the security mechanism of the trap panel and realizes what the 'trick' to the thing was:
The stone in front of the secret panel removed the security mechanism from the darts traps, while the one in the middle of the cellar opened said panel to the light. So one could without troubles open the panel while being in the middle, carefully avoid the stone in front of the panel and retrieve what was needed, before closing it once more by clicking again on the stone in the middle and leaving.
A bit complicated and costly, so there has to be a good enough reason for it.
And indeed there is.
Within the chest there appears to be three tiny black vials filled with a dark sort of tar-like liquid.
You count two green colored liquids near the tiny chest in pyramidal based vials, bunched together with three small pots of some sort of salve. There is also a small bottle of what looks like oil in the corner of the small secret stash.
Within the chest, apart from the vials, there are also 327 gold pieces, 33 silver pieces and 45 copper pieces, together with a small white pearl whose value is approximatively of one-hundred gold pieces.
You have no idea what the various salves or vials contain...but the black ones do look a bit ominous.