The Finnish "mauste" applies to both, herbs and minerals. The Finnish Wikipedia says so: "Mausteet voivat olla voimakkaan makuisia tai voimakasaromisia kasvin osia, kasvista eristettyjä ainesosia tai mineraaleja."
Same in my native German, where "Gewürz" applies to everything you can season a dish with (although not according to science, but in the vernacular). So, "seasoning" might be the better translation.
I came to say that salt is probably not a spice and is definitely a condiment. I didn't foresee other people classifying it as a seasoning. Maybe condiment is slightly more British/Australian and seasoning is slightly more American? At least as regards to defining salt?