Aluminum Wiring???

Solid aluminum wire was used in residential electrical systems in the 1960s and 1970s, but is now considered a potential fire hazard:

Weaknesses: Aluminum is more likely to become defective than copper, and can separate from screws in outlets, switches, and light fixtures.

Poor connections: Poor connections can cause the wire to overheat, which can lead to a fire.

Insurance: Single-strand aluminum wiring may void a home's insurance policy.

Fire hazard conditions: Homes with aluminum wiring are 55 times more likely to have at least one outlet connection that reaches fire hazard conditions.