marcasite

n [C, U] (piece of a) type of crystallized mineral, used as jewellery 白铁矿, 白铁矿石（用作饰物）: [attrib 作定语] a marcasite ring, ie a ring with a marcasite set into it 白铁矿石戒指.

Manx cat, Manxman, many, many a, many-sided, Maori, map, map-reader, maple, maple sugar, maple syrup, maquis, mar, marabou, maraschino, marathon, marauder, marauding, marble, marbled, marbling, March, march past, marcher, marches, marchioness, Mardi Gras, mare, margarine, margin, marginal, marginally, marguerite, marigold, marijuana (also marihuana), marimba, marina, marinade, marine, Marine Studio, mariner,