Yellow Heart

A yellow or gold colored heart, frequently used alongside other colored hearts. 

Amusingly, this emoji displayed as a pink hairy heart on Android 4.4. It has been suggested that this visual oddity was created following a misinterpretation of Unicode's black-and-white reference images.

As with the other color-based hearts, this emoji is often also used to express an affinity with or appreciation for various people, places, groups, objects, or ideas associated with the same color.

On Snapchat, this emoji next to a contact denotes a person that you snap the most, and who also snaps you the most (#1 best friend). The yellow #1 BF heart turns into a red heart after two weeks.