Spiritual Stone of Water

The Zora's Sapphire is the Spiritual Stone of Water which was passed down to Link by Princess Ruto after he had saved her from inside of the giant fish Lord Jabu Jabu, who had been posessed by Ganondorf's evil. After Link had saved her, she actually fell in love with Link and gave him this stone as a symbol of their engagement.

It is one of the three Spiritual Stones which Link needed in order to open the doors to the hidden parts of the Temple of Time, where the Master Sword rested.