giyhonite
Giyhonite is a fictional mineral that appears in the novel "The Atlas of Impossible Places" by Carissa Broadbent. Within the narrative, giyhonite is described as a rare and potent substance with luminous properties. Its primary characteristic is its ability to glow, emitting a soft, ethereal light. This luminescence is not constant but is said to be influenced by the emotional state of those nearby, intensifying or dimming in response to feelings.
The mineral is also attributed with a significant role in the magical or technological systems of the