The colors of rubies and emeralds are so striking that they define shades of red and green—ruby red and emerald green. But ...

One feature of compounds made with transition metals is their intense colour. There are many examples in nature, including ...

Both rubies and emeralds are minerals, which is a type of rock with a consistent chemical composition and a highly ordered ...

The invention is a process for recovery of hexavalent chromium from waste streams. The method is reacting non-toxic precipitating reagent with the hexavalent chromium to form an insoluble precipitate, ...

A browse through images of chromium compounds on Wikipedia shows a whole spectrum of colours: dark red chromium(VI) oxide, orange-red lead chromate, bright yellow sodium chromate, brilliant chrome ...