Another exceptional gem is red beryl, renowned for its vibrant red hue, which results from manganese ions and trace elements ...

At room temperature Chromium has a bcc (body-centered-cubic) crystal structure with a basis of one Cr atom. The unit cell is illustrated. E = 248 GPa.

The chromium replaces about 1% of the aluminum in the corundum or beryl crystal when a ruby or emerald forms underground at a high temperature and pressure. But how can one element—chromium ...