Pyrite has been used for centuries both in jewelry and as an ore of iron. The material is very brittle and heat sensitive and requires some care in cutting, so Pyrite jewelry is not as common as its natural occurrence. In this article let us explore how to identify if a Pyrite is Real or Fake.
Here is an Easy guide to telling apart Real Pyrite from common fakes and adjacent minerals Gold, Copper, and Marcasite
Let us understand about few characteristics of Pyrite before we move on.
Pyrite is of iron sulfide mineral that gets its name from the Greek word for fire because of its sparks when struck like a flint. It is the most abundant sulfide mineral found on earth and occurs in nearly all rock types and most geological environments.
The term ‘fool’s gold is often used as an alternative name for Pyrite, a glittering golden mineral of iron and sulfur.
This may not mean much, but the bright golden crystals of pyrite contrast markedly with the usually subdued gray, brown, and black hues of common rocks, which has historically given it bad repute among other minerals of significance.
Since gold has been valued excessively, some may say that this confusion has created a wealth of tales about Pyrite being mistaken for gold for much of history.
Unfortunately, it has also created an industry, especially in medieval times, of charlatans making money by selling Pyrite as gold, claiming that they can change Pyrite into gold, or producing gold from other materials in their laboratories.
The idea behind the term fool’s gold is that people could be fooled into thinking that Pyrite, which is often worthless, was something highly valued.
Due to its geological abundance and historical reputation, there is not much incentive to sell other materials as Pyrite or synthetically produce it.
Since Pyrite is most commonly found as inclusions in other more valuable minerals like Lapis Lazuli, imitations like copper and resin are sometimes used to fill fractures and cracks and marketed as Pyrite.
If you are buying a gemstone that has alleged pyrite inclusions or just Pyrite itself, there are a few distinct physical features that you can look for to identify real from fakes.
How to Tell of Pyrite is Real or Fake?
Conduct a Hardness Test
Real Pyrite is significantly hard, with a range of 6-6.5 on the Mohs scale. You can test this either by using your Pyrite stone to scratch glass or using a knife and scratch the surface of the stone itself.
Real Pyrite is hard enough to withstand a knife without any scratches on its surface.
Real Pyrite will also readily scratch glass. This is an efficient test of authenticity because common substances used to imitate Pyrite like copper are much softer (hardness of 3 on the Mohs’s scale) and are therefore easily scratched by a knife or switchblade.
Conduct a Streak Test
Another efficient test of Pyrite’s authenticity is the color of the streak it produces when scraped against a white unglazed porcelain tile.
For this test, you will need your stone and a piece of porcelain tile called a ‘streak plate’ among gemologists.
This is a slightly destructive test in that it crushes parts of the stone’s surface to powder. Real Pyrite, despite its hardness, is extremely brittle.
This means that it powders easily to produce a greenish-black streak against the tile.
If your stone produces a white streak or none at all, you can be assured that it is not Pyrite.
Additionally, another significant mineral that is also an iron sulfide and very closely resembles Pyrite in some physical properties is Marcasite.
The streak test is also an efficient way to distinguish between Pyrite and Marcasite. While Pyrite produces a greenish-black streak, Marcasite has a gray streak.
Observe the Coloration
While Pyrite is the most commonly occurring form of iron sulfide, it is often confused with other iron sulfides like Marcasite.
The easiest method to distinguish between these two iron sulfide components is their distinctive coloration.
While Pyrite is brassy yellow, oftentimes with an iridescent tarnish, Marcasite has a tin-white appearance, which darkens when exposed to air.
Observe the Marcasite ring pictured above. While Marcasite tends to have a lighter brass color than Pyrite, it tarnishes darker than Pyrite. Its streak is gray, whereas Pyrite may have a greenish-black streak.
Observe the Structure of the Crystal
Pyrite’s crystal structure is what truly sets it apart from minerals it runs the risk of confusion with, such as gold and, more often, Marcasite.
While neither of these technically qualify as Pyrite imitations, as a crystal buyer, it is essential to understand the crystallography of a stone you are buying to land a high-quality one that is worth the buck.
- Pyrite is easily distinguishable from real gold in that it forms isometric crystals, often cubic, while gold occurs as tiny flakes or rounded nuggets.
- Pyrite crystals are either cubic or the 12-sided forms called pyritohedron. Pyrite crystals that occur in a block formation are commonly found in slate and phyllite.
- Marcasite is formed at relatively low temperatures in chalk rocks as well as in hydrothermal veins that mostly host zinc and lead minerals. It doesn’t form the cubes or pyritohedron typical of Pyrite, instead occurs in groups of spearhead-shaped twin crystals also called cockscomb aggregates.
Check for the Density of the Crystal
One way to identify fakes is to check for stone density. Although you cannot measure the density of your stone directly, you can differentiate between less and more dense items by lifting them in your hands.
Real Pyrite has a mineral density of about 5.0-5.03, while copper, which is confused for and mismarketed as Pyrite, is way denser with a specific density of 8.96.
You can ask your jeweler to measure these for you. Fake Pyrite made with such substances as resin and Marcasite is also much less dense than a real stone.
Check for the Odor
When rubbed vigorously with any hard substance, Real Pyrite would produce the smell of rotten eggs due to the presence of sulphuric acid. But this is a destructive test, so be careful before you conduct it.
Inquire for the Place of Origin
Asking your seller where a given stone originates is Pyrite crystals are fairly abundantly found.
Fine crystals are known to develop from the following localities: Leadville, Colorado, French Creek in Pennsylvania, Bingham in Utah, Elba in Italy, Spain, England, Austria, Germany, Switzerland, Sweden, Peru, and Bolivia.
Observe the Size of the Crystal
Pyrite is usually seen in inexpensive jewelry, faceted in rose-cut fashion with flat backs, similar to the older marcasite jewelry popular during the Victorian era.
Cabochons of any size are cut from the large Pyrite crystals. Another rare Pyrite formation is what is marketed as ‘Pyrite dollars’ or ‘Pyrite suns‘, exhibiting striations radiation out from the center like sun rays, as shown in the adjacent picture and in the cover photo for this article. These consist of nodules of pyrite crystals that grow between layers of shale or coal.
Such a formation grows from a central point, squeezed flat between shale layers. Such a formation is called a ‘radiating habit’ and can have crystals of any form, from blocky to fibrous.
When it occurs in radiating habit, Pyrite is found in narrow, compacted seams of slate interbedded in 300 million-year-old coal deposits. For centuries, people believed that pyrite suns were fossils that had undergone pyrite replacement.
Currently, we know that they are simply formed due to the enormous heat and pressure compacting the slate, causing Pyrite to grow laterally in a radiating manner.
In this article, we have listed the several ways in which you can identify Real Pyrite apart not only from fakes made of resin and copper filings but also from adjacent minerals like Marcasite.
While a streak test is often the most sure-shot way to establish the authenticity of Pyrite, not only may it cause some powdering to the rock, it could also be hard to grasp for the amateur rock buyer, given that the streaks of minerals like copper and some other iron sulfides may appear similar, with very subtle differences in color for the untrained eye to catch.
If the streak test is not viable for you, rely on your rock’s hardness, density, and crystal structure to make sense of its authenticity. Some fakes are so light that when you hold them in your hand, you can tell that there is something suspicious about it. In such a case, you need to verify the hardness of your stone and perhaps inquire where it originates from.
While it is well-known that Pyrite is the most commonly occurring sulfide mineral on the earth’s surface, not many know that this mineral is perhaps only possible on the earth’s surface due to the presence of atmospheric conditions unique to the atmosphere of the earth.
While the solar system contains many similar combinations of sulfur and iron, none of them have the chemical properties of Pyrite. Jupiter’s moon Io, for example, is perhaps the most volcanically active body in the solar system, and its volcanoes are powered by sulfur.
Therefore, the shiny crystals of this humble mineral provide a record of the past, help explain the current environment and allow predictions of what will happen in the future.