sentence: Tellurides are normally the main ore of tellurium.
sentences_before: They are strong reducing agents.
sentences_after: Most natural tellurides are not pure, so they are much less reactive. They are the rarest oxidation state. They are weak oxidizing agents, that can be reduced to tellurium. Tellurites are made by reacting tellurium dioxide with a metal oxide. They are powerful oxidizing agents.
concept_name: telluride
headings: Tellurium Properties Chemical compounds
categories: Semimetals