marcasite
/ˈmɑːkəsaɪt/noun
1- a semi-precious stone consisting of iron pyrites白铁矿石（一种次贵重宝石）。
1.1
- mass noun a bronze-yellow mineral consisting of iron disulphide but differing from pyrite in typically forming aggregates of tabular crystals黄铁矿。
1.2
- a piece of polished steel or a similar metal cut as a gem磨钢装饰石。
词源
late Middle English: from medieval Latin marcasita, from Arabic marḳašṯa, from Persian.