Assertion: neptunium | /r/HasProperty | discovered
Facets:
Source sentences:
text: Neptunium, however, was discovered significantly later in history than either of its periodic table neighbors, and is not widely used.
text: Once Np was discovered, Pu could be readily discovered (and it was the next part of the story: I have no idea why actinide splits the discoveries at Np, given that Np leads immediately onto Pu)
text: When neptunium was first discovered, scientists thought it was an entirely artificial, or man-made, element.
text: Neptunium was considered to be entirely artificial when it was first discovered.
text: Neptunium was considered to be entirely artificial when it was first discovered.
text: When neptunium was first discovered, scientists thought it was an entirely artificial, or man-made, element.