Cobalt Jade, I quite like costume 2, very appropriate.

I definitely imagine something that has both flowy and structured elements. The bodice in the Baynes illustrations looks quite structured and solid while the skirt and scarf flow. The crown is massive and heavy, but her hair is wild, the perfect blend of strength and movement. 

Lu Valiant, MINOAN is exactly what I was trying to think of! (careful googling it everyone, it’s revealing, don’t want that part) It has the right colors and structure. I also like something a bit ancient Babylonian (others have said Persian).

The other thing to consider is layers that can shift and alter throughout the movie so that it doesn’t get boring. A robe/cape to wear over everything at first, more sashes and drapes and jewels after “shopping” with uncle Andrew, etc. 

I recently rewatched Return To Oz, and I think a costume akin to something like the villainess Mombi could be rather interesting for Jadis.

• Mombi (Return To Oz)

@rilianix Ooh yes, though preferably without the interchangeable heads!! I loved that movie when I was a kid — it's just amazingly surreal and creepy.

@courtenay Haha yes! And I know right, the Wheelers especially were so creepy! 

In terms of the costume, I just think it feels beautiful but dangerous, which I think would be especially perfect for Jadis, just as it was for Mombi in the movie.

Yes, I, too, enjoyed the rather creepy Return to Oz, especially the mandolin music that Mombi played, in that room with all the cases of other people's heads. Doesn't it remind you a bit of MN's Hall of Statues? 

I was idly looking at Origin stories of the most iconic department stores, including Harrods, Selfridges, USA's Bloomingdales, not to mention Sak's 5th avenue, Macy's and even David Jones, which started in Sydney in 1838, & is the World's oldest continuously operating store, trading under its original name. For Italy's La Rinascente I found this poster, from 1877 & 1883, when this department store expanded to Rome. The way the lady is attired in it, just screams Jadis, especially the sort of service she seems to demand of staff, & the rather haughty look she is depicted as having. Despite being in just the right attire for the likes of Aunt Letty to call her a brazen hussy?