What is Marcasite Stone/Rock Jewelry?

The name comes from the Arabic name for the general name for pyrite (Markaschatsa). Somehow we have got stuck with this corruption of the Arabic name which does cause some confusion, especially since there actually is a mineral called marcasite that is so similar to pyrite, while this may by confusing, the reason is that until about 1845 they were classed under the same name scientifically.

The name comes from the Arabic name for the general name for pyrite (Markaschatsa). Somehow we have got stuck with this corruption of the Arabic name which does cause some confusion, especially since there actually is a mineral called marcasite that is so similar to pyrite, while this may by confusing, the reason is that until about 1845 they were classed under the same name scientifically.

Marcasite jewelry is made from small faceted pieces of pyrite, or iron pyrite, usually set in sterling silver. So when it comes to marcasite jewelry and pyrite is used as a gemstone, it is referred to as "marcasite".

While Marcasite jewelry has been around since ancient times, they jumped in popularity in 17th Century France when Louis XIV decreed only he should wear diamonds. Again particularity spiked in the early 18th Century, the Victorian Era and World War I through the Art Nouveau period and in particular in Art Deco jewelry.

It was often used as a replacement for diamond jewelry because it was cheaper, especially in those times of either economic difficulty or as in Victorian times where there were more people enjoying a more middle class affluence then in previous times.

Though usually set in silver there is some lovely marcasite jewelry that either has gold accents, or is set in gold creating gold marcasite jewelry.

One of the great things about marcasite, is how well it accentuates other gemstones. I especially like how opal and turquoise go with it, but close favorites are garnets, rubies and aquamarines.

Good Jewelry is easy to find as the is a good selection of both factory and handcrafted marcasite jewelry that are elegant, well crafted and sophisticated and yet still very affordable.

The actual mineral named marcasite (white iron pyrite), though also an iron sulfide has an orthorhombic crystal structure and is pale yellow to almost white or gunmetal gray color and has a bright metallic luster.

The color easily tarnishes to a yellowish or brownish color and gives a black streak when exposed to the atmosphere. Its almost spear like crystal structure makes it brittle, fragile and crumbly and therefore unsuitable for jewelry making.

Marcasite reacts more readily than pyrite under conditions of high humidity, forming a white powder. This deterioration is called "pyrite decay". Keeping the stone under low humidity (less than 60%) storage conditions prevents or slows the reaction.

Though not used for jewelry, marcasite can have some wonderful formations that can be very interesting. This makes it a popular stone for rock collectors.

Marcasite is polymorphic to pyrite, thus has the same composition, but a different crystal system. Above 400 ° C, marcasite transforms to pyrite.

image from wikipedia.org

Pyrite (fool's gold) is also an iron sulfide butt with a cubic crystal structure. the stone has a metallic luster and pale brass-yellow hue, hence its common colloquial name "fool's gold". 

The name pyrite is derived from the Greek word  πυρίτης (puritēs). In Rome this was the general name of a few stones that caused a spark when struck against steel.

Chemically, it is the cubic modification of iron disulfide with a chemical composition FeS ₂, and thus consists of iron and sulfur in the ratio of 1 to 2.

It's more cubic structure makes it more stable and easy to cut, thus it is the gemstone used to add to jewelry pieces creating marcasite jewelry.

Due to its metallic luster and its golden color it was often confused with gold. Unlike genuine gold it is not easily moldable, pyrite is substantially harder than the noble metal.

With a Mohs hardness of 6 to 6.5 Pyrite is one of the hardest minerals of similar minerals and can barely be scratched with a steel file.

Interestingly enough, many a pyrite vein will also contain traces of gold, but not usually in quantities enough to make mining the gold commercially viable.

In marcasite jewelry, the pyrites are usually cut to look like diamonds and is used often in combination with other gems and metals like silver and are then set into elaborate designs. The contrast between the two metallic shades of gray, creates a combination that is stunning with a dramatic vintage look.

Most common designs are geometric, filigree or paisley. Though maybe more traditional, marcasite jewelry tends towards the bold and dramatic without being overwhelming. Often pieces have a tarnished look, which adds even more of their special appeal.

image from wikipedia.org