Blue Flame

Blue Fire is an exotic item featured in, not to be confused with the Blue Candle. The only function of the uniquely-colored fire is to melt Red Ice.

Summary
An empty bottle is needed to store Blue Fire, which is then dumped near Red Ice to "melt" it. The flame is found in Ice Cavern and Ganon's Castle. It can also be bought from a candle at the Medicine Shop for 300 Rupees. In Master Quest, Blue Fire can also be found in the Gerudo's Training Ground.

Blue Fire is required in Ocarina of Time to progress. It is used to complete the Ice Cavern and obtain the Iron Boots. It is also used to get the Zora Tunic by melting Red Ice throughout Zora's Domain. Both items are needed to enter and complete the Water Temple. As mentioned before, it reappears in Ganon's Castle and is used to solve the Water Trial.

Trivia

 * Keese will become Ice Keese if they fly through Blue Fire.
 * features a similar object which "burns" the boomerang and can be used to freeze water. This fire cannot be contained or carried around.
 * In the book Harry Potter and the Philosopher's Stone by J. K. Rowling, there is a spell which creates a blue flame that can be stored in a bottle.