You can do something similar on a car. They are commonly called "candy", Candy apple red being the most famous. You start with a metallic base coat which is topped off with a translucent color coat then a clear coat. Depending on how Disney does this, the spires could actually sparkle in sunlight.I've been involved in theater for much of my life, and priming with silver is a method we often use to make the top color look brighter, shinier and/or more metallic.