Occurrence and Production
Only minute traces occur naturally in the Earth's crust as a spontaneous fission product in uranium ores. A kilogram of uranium contains an estimated 1 nanogram (10−9 g) of technetium. Some red giant stars with the spectral types S-, M-, and N contain an absorption line in their spectrum indicating the presence of technetium. These red-giants are known informally as technetium stars.
Read more about this topic: Technetium Compounds
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