Archer's Ring of Elemental Power

This gold ring has small arrows engraved all around the inside. Four gemstones are set in the top of the ring: a ruby, a diamond, a sapphire, and an emerald. They all have a bright shimmer. The ring has four charges. You can use a charge to add 4d8 fire, cold, lightning, or poison damage to the damage roll of one ranged arrow attack. There is one charge for each damage type. You must declare that you are using a charge before making the attack roll and the charge is expended whether the attack hits or misses. When a charge is expended, the corresponding gem loses it's bright shimmer (ruby for fire, diamond for cold, sapphire for lightning, and emerald for poison). The ring's charges reset at dawn.

Notes: Damage: Fire, Damage: Cold, Damage: Lightning, Damage: Poison, fighter or ranger with the archery fighting style