Here's a pic from the "Pictorial History of the Blue Angels". Also one from the squadron book.

The edge is polished aluminum.

None of the pics I have seen have ever shown a yellow leading edge on any Blue Angel airplane. Even Beetle Bomb the all yellow Bearcar is shown with the polished metal leading edge.

BTW, if they gold leafed the script it was real gold. I gold leafed a few things in my past life as a sign painter.