The price for weapon elixirs has steadily dropped since the new alchemy feature came out. Today, I see a few people selling for 185k and 180k each. I have stocked up 20 @ 180k and 10 @ 185k.
I think the price drops because people need more money for elements and tablets/stones. Also, the astral feature has reduced the needs for weapon elixirs greatly. That's my theory.
I wonder is the same phenomenon happening to other servers as well?