Blue Sapphire

Blue Sapphire is a mineral mostly mined from Small Thorium Veins or Rich Thorium Veins.

Source
Blue Sapphires can be found in a variety of places.
 * Thorium Veins
 * Prospecting Thorium Ore and Mithril Ore.
 * Drops from high level mobs.
 * Inside various chests.
 * Blue Sack of Gems
 * Thaurissan Family Jewels
 * Bloated Salmon

Blue Sapphire as an ingredient
Blue Sapphire is used in the following recipes:

Blacksmithing

 * Thorium Armor
 * Dawn's Edge
 * Demon Forged Breastplate
 * Serenity
 * Corruption (sword)
 * Storm Gauntlets
 * Enchanted Thorium Leggings
 * Frostguard
 * Lionheart Helm
 * Stronghold Gauntlets
 * Inlaid Thorium Hammer

Engineering

 * Gyrofreeze Ice Reflector
 * Dark Iron Rifle

Jewelcrafting

 * Sapphire Signet
 * Emerald Crown of Destruction
 * Sapphire Pendant of Winter Night

Blue Sapphire as a quest item
Blue Sapphire is needed for the following quests: