Crystal Vial

Crystal Vials are a crafting reagent used in a very large number of alchemy recipes—primarily potions, elixirs, and flasks. They're also used by enchanters to create Lesser Mana Oil and Wizard Oil.

Source
This item can be purchased from trade goods vendors, alchemy suppliers, and others. It can also be contained in Alchemist's Cache and can be rarely fished up in Dalaran.

Any existing Empty Vial s that were in players' bags before patch 4.0.3a were turned into Crystal Vials.

Objective of

 * Mending Old Wounds: Crystal Vial (4)
 * Taking Precautions: Crystal Vial (5)
 * Vial of Visions: Crystal Vial (1)