Obsidian prices @ rare trader

Did I really see this? I just went to sell some obsidian @ the rare trader in Lions Arch, it's selling for over 4k but the trader will only buy it back for 100g? How does that make any sense???

Anyone out there see some sort of logic behind that, or is it just me?

It just does that everynow and then, go back after a few minutes.

I would hope thats true, we'll find out in the morning.

Earlier today:
deldrimor steel: 1.03k
Leather: 100g
Steel: 204g

Present:
deldrimor steel: 549g
leather: 30g
steel: 30g

Lets see what they do 7 hours from now...

I've seen several times where the dye trader buys all my dyes 1 gold
just wait a little