New archaeological findings in the Great Basin region of North America have identified a series of obsidian-lined stone mirrors used by ancestral Indigenous groups 3,500 years ago. These mirrors were positioned in high-altitude rocky outcrops to capture the reflection of summer lightning strikes. This practice is now being linked to the "First-Thunder" rites, a tradition dedicated to summoning the seasonal rains that sustained the desert ecosystem.
The study highlights how ancient peoples used the reflective properties of volcanic glass to create a physical connection with atmospheric phenomena. By documenting the precise orientation of these mirrors, archaeologists have confirmed their alignment with the predominant direction of incoming monsoon storms, proving a sophisticated understanding of local weather patterns and their ritual importance.