It creates a small area of heat up to five centimetres across which then burns a hole in that object, as if a candle were being held just underneath it. This spell can be used on living beings-though they tend to notice the heat before it can get too serious, and pull their hands with a small shriek. This spell is most commonly used to light a candle or start a fire in a grate. The invisible flame can last for up to three minutes.
- Blacksand! - p. 37-38