Ryza Rust vs Sahara Yellow

How close are they?

ΔE 18.3, loose: different enough that you should pick on purpose. Sahara Yellow is a little darker, more muted, cooler than Ryza Rust.

Can I use Sahara Yellow instead of Ryza Rust?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Sahara Yellow is a little darker, more muted, cooler than Ryza Rust.

Can I use Ryza Rust instead of Sahara Yellow?

The same difference applies the other way round: Ryza Rust is a little lighter, more saturated, warmer.

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.