Exoskeleton Reference Libraries
Aragonite is a polymorph of the mineral calcite, both having the chemical composition CaCO3. Its structure differs from calcite and leads to a different crystal shape, an orthorhombic system with acicular crystals. By repeated twinning pseudo-hexagonal forms result. It may be columnar or fibrous, occasionally in branching stalactitic forms called flos-ferri (flowers of iron) from their...
- Bad luck; misfortune.
- The smallest amount possible or the most worthless thing.