FYI for everyone, just in case any of you would like to have your characters interact or use one of the jewels, this might help you:
To use a jewel, the user must be of the same element, not a branch or veration of it, the actual element. For example, electricity is a branch of fire. If you're not from said element, the physical impact is greater as a punishment for using it.
Next, it has big collateral damage to use it. Clear example is the first time Azumi used the water jewel. It shattered her arm in various parts with one simple use.
Then, the benefits. The jewels increases the user's magic/physical power and speed/cast speed.
Also, each jewel was created by the god of it's element. (Again thank you
@ThePlayfulFox for those). So can your character have a vision or encounter with said god? Yes, but you must send me a pm saying why and what plans you have for it.
Now regarding the Crowns. (I feel this is necessary for the new people and since Wes is back). The Crowns, like the jewels, power up the user, but it's defenses only. Magical and physical defense. If the owner, example Azumi, is joined with their soulmate and has the qualities to become King or Queen, part of the powered is shares. For example, since the Kelan crown has 34% of the original power (Remeber the crown used to be one and it got divided into three, Kelan, Creel and Parral) and since Azumi married Wes, he has 14% of that power and Azumi 20%. This is why Kings or Queens can use the jewels longer without taking damage, because of the boosted defenses.
In Wite's case (since thinking about this inspired this post xD) she being in the demon world should give her boosted magical and physical power, but not as much as a jewel would. But enough to ware down a crown owner. Plus the terrible atmosphere doesn't allow the queen or king to last long, they can longer then anyone else, but will get tired quickly. Wes versus Wite looks really interesting, I hope this info is considered while it happens.