Essence of Nightlight is an Alchemical Extraction. It can be combined with any Suspension to create a 
Hearthlight Bomb.
In his troubled 
Underdark days, the drow with the heart of gold, Drizzt Do'Urden, often purified nightlight to draw out its luminance. By its light his face was pensive, thoughtful, and too - wise.
Properties
Single Use
Rarity: Common
Weight: 0.1 kg / 0.2 lb
Price: 10 gp 
UID
ALCH_Extract_NightlightUUID
83b2f9b8-9f69-41c3-a2b8-d3b34fea9f33
Where to find
Crafted by combining 3 
Nightlight Fronds