The following die is light black plastic, with gold paint on the carved side icons, and is 0.5 inches in length, width, and height.
These aren't from an RPG, they are from the Star Wars Galactic Battle Game by Hasbro. Clearer image:
The symbols on the dice correspond to skills. Rolling the die grants a bonus to the corresponding attribute. Each card has its own list of bonuses, but lists all the attributes and their corresponding symbols: