Ryza Rust vs Orange Glaze

How close are they?

ΔE 15.9, loose: different enough that you should pick on purpose. Orange Glaze is noticeably lighter, more muted than Ryza Rust. They are different kinds of paint: Citadel Ryza Rust is an opaque base/layer paint and Two Thin Coats Orange Glaze is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Orange Glaze instead of Ryza Rust?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Orange Glaze is noticeably lighter, more muted than Ryza Rust. They are different kinds of paint.

Can I use Ryza Rust instead of Orange Glaze?

The same difference applies the other way round: Ryza Rust is noticeably darker, more saturated.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.