Anniversary issue: "Swiss Confederation 700 years"
There are two minor varieties of this coins edge lettering:
KM# 71.1: "CONFOEDERATIO HELVETICA ++ 1291 – 1991 ++"
KM# 71.2: "CONFOEDERATIO HELVETICA ++ 1291 ÷ 1991 ++
This is the first type with "1291 - 1991"
Mintage: 297,741.
200,000 were recalled and melted down due to poor quality.