Synthetic stones are created artificially in a factory or laboratory, but have the same physical, chemical and optical characteristics as their natural counterparts. These stones usually have high luster, and is difficult to tell the difference from natural stones with the naked eye.
Marcasite The mineral marcasite, sometimes called white iron pyrite, is iron sulfide (FeS2) with orthorhombic crystal structure. On fresh surfaces it is pale yellow to almost white and has a bright metallic luster. It tarnishes to a yellowish or brownish color and gives a black streak. It is a brittle material that cannot be scratched with a knife. It typically forms under low-temperature highly acidic conditions.