Vial of Blood is a common Miscellaneous item. Primarily of use for bartering or sale to Traders.
Blackened drops of blood have coagulated on the outside of the bottle and stained it's stopper.
Properties
Miscellaneous Items
Rarity: Common
Weight: 0.1 kg / 0.2 lb
Price: 1 gp
Effect
When destroyed, creates a 
Blood surface.
Area: Blood
AoE: 1 m / 3 ft (Radius) 
Type: Where to find
Found throughout the game as set-dressing and random loot.