Pyrite is the classic "Fool's Gold" . There are
other shiny brassy yellow minerals, but pyrite is by far the most common
and the most often mistake for gold . Whether it is the golden look
or something else, pyrite is a favorite among rock collectors. It can have
a beautiful luster and interesting crystals.
It is so common in the earth's crust that it is found in almost every possible environment, hence it has a vast number of forms and varieties.
Bravo rite is the name given to a nickel rich sulfide. It is closely related to pyrite but contains up to 20% nickel. Some mineral books treat it as a variety of pyrite.
Pyrite is a polymorph of marquisette, which means that
it has the same chemistry, FeS2, as marcasite;
but a different structure and therefore different symmetry and crystal shapes. Pyrite is a difficult to distinguish from marcasite when a lack of clear indicators exist.
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