One provides you insight and reveals the unknown, the other provides the burnination of all you survey. Only you can decide which Gem of S’ing is the right Gem of S’ing for you.
Gem of Searing
Wondrous item, very rare (requires attunement)
This gem is a round, red crystal that would fit snugly into sights for a bow or crossbow. As a bonus action, you can speak this gem’s command word and cause the front of the ranged weapon to which it is attached to glow with an intense, red heat. This light illuminates a 40-foot radius and dim light for an additional 40 feet. While the bow or crossbow is heated, it deals an extra 2d6 fire damage to any target hit by a bolt or arrow from the weapon. The heat and light last until you use a bonus action to speak the command word again or until you drop of holster the weapon.