Spinel, MgAl 2 O 4 (download cif), is a rare gemstone that was used to imitate rubies. The structure has face-centered cubic symmetry, and is a little heavy to understand. The general formula is AB 2 ...

Mars expert Roger Wiens and his team, including the rover Perseverance, discovered fascinating rocks incorporating kaolinite and spinel on Mars’ surface that form in warm, wet environments — but the ...

The research focuses on a series of chromium-based spinel oxides (ACr 2 O 4), where transition metal elements occupy tetrahedral sites, exhibiting varying POD-like activities. By calibrating t 2 ...