Marcasite - The Different Colors, Sizes and Shapes

Marcasite has been known to the world since the beginning of civilization. For instance, the Greeks used it as a talisman and the Chinese mined it quite frequently. Mayans and Aztecs also used the stone, which today is still used to create certain types of ornaments.

Marcasite is Iron Sulfide, which is written scientifically as FES2. The name of Marcasite has been very popular, especially when associated with silver, however for the most part, when most people are referring to Marcasite in silver and other gems, they are actually referring to Pyrite with is a polymorph of Marcasite.

Polymorphs are very interesting, a polymorph of a mineral is when two minerals are made of exactly the same chemical compounds; however they are arranged or structured differently. This structure might have a lot of similarities, but the two minerals are ultimately different. Another common polymorph are diamonds and graphite.

Marcasite is a yellow or a yellow brassy mineral. It also comes in hues of green. It is usually lighter and softer than Pyrite, its polymorph. Marcasite is not really used for jewelry because it crumples easily and certain times it can decay. It can literally turn into powder within a few years, while doing so it smells from sulfur (rotten eggs). However, there are certain ornaments that are created from this mineral, many of which come from Native Americans. Marcasite can come in big chunks, but most are small rock sized. One of the unique feature of Marcasite is the cocks comb. It is created when Marcasite crystals are twinned. It truly does look like a rooster’s head.

How and Where is Marcasite Formed and Found?

Marcasite is an interesting mineral that is made from iron. Its scientific formula is FES2 and it is well known as Iron Sulfide. Marcasite is closely associated with Pyrite and is considered a polymorph. A polymorph cans happen quite frequently in the world of minerals. For instance, both Marcasite and Pyrite have the exact same chemicals present, the only difference being is that Marcasite’s chemicals are structured differently, ultimately making its attributes similar but different to Pyrite.

Marcasite is found frequently near bands of irons and does have a crystal structure, which is opaque. Marcasite is commonly and incorrectly used to denote Pyrite, especially when mixed with silver. Marcasite has a beautiful yellow or yellow brass color and can sometimes comes in the hue of green. While it has a hardness score of 6.5, it can crumble quite easily and certain Marcasite minerals tend to decay easily, turning into powder over the course of a few years.

One of the unique features of Marcasite is the twinning feature of its crystal formation. This twinning feature is sometimes called the Cox’s comb, because it resembles a rooster’s head. This unique feature is only available on Marcasite.

Marcasite is lighter than Pyrite which is usually more golden and is found in many other minerals, most notably Lapis Lazuli.

Marcasite is fairly common and can be found in the following regions; Mexico, Peru, France, China, Russia, the United States and England. It was known to the ancient Greeks, Chinese and Mayans.