Those extra shiny strings are aluminum-wound, somewhat of a novelty in the late 1960’s when this piano was built. Though these have held up well, aluminum-wound strings as a rule have never caught on and are all but extinct now.
In this case, the aluminum winding was seen as a “transition” from the copper-wound bass strings to the plain wire treble strings. Manufacturers have tried dozens of different ways of bridging this transition point over the years, with varying results.
Gordon Laughead was a small, family-run, Michigan-based piano manufacturer that operated from the 1940’s until the 1970’s. They made good quality pianos, and this particular one was a testament to that fact. Unfortunately, like hundreds of other piano manufacturers, they eventually succumbed to an over-crowded market.