Unfortunately, there is nothing about this situation that Dubi Gan read about...
Miu looked down the well using his ruby crystal. He wasn't sure if the angle of the sun, the alignment of the stars, or maybe the properties of the stones lining the well, but he saw magic clearer than he had in a long time. At the edge of his vision was the white glow of Frog Froth's blessed sword. Down the well, he could see how a faint amount of magic was leaking from the metal chest - it wasn't magical, but something inside was.
And the water... the water wasn't magical. But there clearly was a creature - or creatures - in the water that had a magical metabolism. It - or they - must have been what was causing those strange ripples!
As you go down, the water gets darker (you're blocking the light) but you are now confident that the water is only 3 feet deep at most. The chains look stout, but they are brass (which can be soft) or bronze (which can be brittle) and you think you can break them.
As you enter the water however, something tries to bite you - or somethings
Holding the chest under one arm, he started climbing out of the well. As he did so, he saw a strange thing. Biting on his rhino leather vest was a two foot long snake - no an eel! - completely transparent, as if it was made of glass. He tried to grab it but it let go and fell back into the water, where its coloration made it essentially invisible. There must be at least half a dozen of these in the water...
Reading the top of the well, pulled up by his companions, Pinpehlu delivered the chest. He was wet and bloodied but otherwise ok.
The green metallic chest was locked and very heavy. However, while sturdy the lock was very simplistic, and a few minutes of poking was sufficient to defeat it.
The chest turned out to be so heavy because it was filled with water. However, inside there was something else - a rotting bag of what must have been a fancy fabric, and inside it, you found a ring of obsidian, about 1 inch in diameter, polished smooth. There seems to be faint runes buried under the surface.
"Let me see those runes..." suggested Dubi Gan after having a look at Pinpehlu's wounds and determining that they were mostly superficial. He was relieved that he had not gotten the porter killed over one little ring, but he hoped that it might prove valuable.
(OOC: the godly palm wine boost visions, not scholarly information. Second sight (detect magic) doesn't need the wine either)
Dubi Gan examined the object.
You couldn't be sure, but you believed this to be an magical artefact (not artIfact, artEfact). The magic users of Yoon-Suin, being bored, rich and scholarly, often experimented with magical items of dubious utility. Over the thousands of years the Yellow City has existed, a number of them have been made, and there are now collectors who will purchase them. So if this is what you think it is, it could easily be sold for several hundred rupees at an auction, perhaps even more!
OR... if you could figure out what it did, perhaps it was useful - perhaps you would want to keep it? But you also know as a scholar that their non-standard nature meant that experimentation would be required - and that could be risky.
OOC: You can do a luck check to get more scholarly information, but you already know this.