One of three props I made for the Legend of King Arthur Challenge.
Concept by Angelina Andreas:
https://www.artstation.com/artwork/EV463N
I modeled this using Maya and sculpted high detail in ZBrush. There are three unique sets of structural and decorative gold pieces that are duplicated around the circumference of the crown for maximum believably + UV efficiency. While developing believable 24 carat gold using Arnold, what ended up being a bit of a breakthrough was figuring out that Arnold's preset gold material uses an incorrect refraction number. I was able to maintain the original base mesh from Maya because the crown only has minor surface corrosion.