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

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

Cattle are ruminants: their stomachs allow them to digest fiber-rich foods like grass and hay. This produces methane, ...

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