Scutch combs and droves are commonly plated with yellow zinc, often giving them a yellow/gold appearance.
The yellow zinc plating helps to stop corrosion by creating a barrier and as a last resort a sacrificial coat. This layer will wear off before allowing the steel to corrode. Zinc is a natural water barrier, so if no water can get to the steel then there will be no corrosion.
If a scutch comb or drove is not plated with zinc then it will corrode at a far greater rate as there is nothing preventing moisture from contacting the surface of the steel.