A rare (but less efficient) kyber substitute, a kohlen crystal, is known for producing an orange blade as well - but these are weaker than normal lightsaber blades. Star Wars Legends stories ...

A lightsaber's color generally comes from the kyber crystal at its heart ... Ahsoka villains Baylan Skoll and Shin Hati had unusual orange lightsabers, but nobody in-universe even blinked.