Is selenium a metalloid?

Wikipedia has a list of 192 metalloid lists, and selenium is shown as a metalloid in 24% of those lists: Lists of metalloids - Wikipedia. Selenium shows borderline metalloid or nonmetal behaviour. read more

The concepts of metalloid and semiconductor should not be confused. Metalloid refers to the properties of certain elements in relation to the periodic table. Semiconductor refers to the physical properties of materials (including alloys, compounds) and there is only partial overlap between the two. read more

Selenium is commonly described as a metalloid in the environmental chemistry literature. It moves through the aquatic environment similarly to arsenic and antimony; its water-soluble salts, in higher concentrations, have a similar toxicological profile to that of arsenic. read more

Selenium, in particular, is commonly designated as a metalloid in environmental chemistry on account of similarities in its aquatic chemistry with that of arsenic and antimony. There are fewer references to beryllium, in spite of its periodic table position adjoining the dividing line between metals and nonmetals. read more