Goddess Cube

Goddess Cubes are mysterious cubes that are scattered all over Hyrule in Skyward Sword. In Faron Woods, a Goron traveller, Gorko, tells Link about these cubes and that the Skyward Strike has an effect on them. When Link uses the strike on the cube, it disappears from the surface world while sending a beam into the sky. The first Cube is found in Deep Faron Woods, and they can later be found all across the Surface in places difficult to reach or hidden from view.

These beams activate special "Goddess Chests" scattered throughout the sky, which contain treasures that are more valuable than those in mundane chests. They can be compared to the larger Chests from Twilight Princess. All items that can be found in these Goddess Chests are difficult or impossible to find though normal gameplay means, including Pieces of Heart, Gold Rupees, and sometimes even a Medal.

Trivia

 * The bird symbol on the Goddess Cubes is the lower part of the Royal Family Crest, the other part being the Triforce.