During "Stronger Than You," the sounds of impact during Garnet's fight with Jasper (punches, hitting the walls, etc) are in time with the beat of the song.
When fused, the gems also fuse their weapons and make a new one.
Garnet's song, "Stronger Than You," has become one of the most popular songs of the entire series, even spawning a music video featuring Estelle (Garnet's voice actor) performing the song.
First appearances of Ruby and Sapphire.
First appearance of Malachite.