Translations:AY Honors/Rocks & Minerals - Advanced/Answer Key/39/en

Tetragonal cyrstal

Tetragonal crystal lattices result from stretching a cubic lattice along one of its lattice vectors, so that the cube becomes a rectangular prism with a square base (a by a) and height (c, which is different from a). Tetragonal crystals include:

1. Wulfenite is a lead molybdate mineral with the formula PbMoO₄. It can be most often found as thin tabular crystals with a bright orange-red to yellow-orange color, sometimes brown, although the color can be highly variable. In its yellow form it is sometimes called "yellow lead ore".
2. Urea is an organic compound of carbon, nitrogen, oxygen and hydrogen, with the formula (NH₂)₂CO. It was the first organic compound to be artificially synthesized from inorganic starting materials.
3. Zircon is a mineral belonging to the group of nesosilicates. Its chemical name is zirconium silicate and its corresponding chemical formula is ZrSiO₄.