Skyrim gemstone meshes, how do they work?

[RatB0Y68]

They seem to be two meshes, an outer & inner mesh. The outer mesh has the textures wrapped around the mesh exterior, giving it a convex look. The inner mesh has the textures wrapped around the mesh interior, giving it a concave look.

I want to replicate this effect for armour pieces, so I can make a 'gemstone' armour set. My question is how do I change the mesh to render its texture on the inside rather than the outside?

[Hanaisse]

There's really nothing special about gemstones, just a trick of the eye. It's two meshes on top of each other with alpha and refraction. It does require an order node in the mesh so it renders properly which I don't believe can be used on an armor mesh.

The same effect can be mimicked with environment mapping (like dwemer or glass armor).