Found still on its card with old Council records.  Purchased ages ago for a set of special Cadette workshops. 

This is one of eight new Cadette Challenge pins earned by girls on their way to a First Class recognition.  It was introduced in 1972 in a pamphlet with a new flexible Girl Scout program for Cadettes.  It was available until 1982, even after a new joint Cadette/Senior program was introduced.

The pin is a clutch back pin with a round metal rim.  On its face it has the name of the Challenge, a trefoil, and a pink ribbon printed on white.

It measures about 3/4" in diameter.