Used as a selective agent in microbiological media to isolate and identify specific bacteria, particularly gram-positive organisms like Corynebacterium diphtheriae, due to its ability to inhibit the growth of unwanted gram-negative bacteria. Commonly added to tellurite blood agar, where pathogenic corynebacteria reduce tellurite to elemental tellurium, resulting in black or gray colony pigmentation, aiding in identification. Also employed in research settings to study bacterial resistance mechanisms and oxidative stress responses. In addition, finds use in electroplating processes and as a precursor in the synthesis of semiconductor materials containing tellurium.