Pyrite Properties, Facts and Photos

What is Pyrite?

The mineral pyrite, also known as 'Fool's Gold', is a sulphide mineral, meaning it's composed of iron and sulphur.

Its metallic lustre and brassy-yellow hue give it a similar appearance to gold. However, several characteristics make it relatively easy to distinguish one from the other.

The most obvious difference is colour because pyrite is not quite as yellow. Regarding weight, pyrite is lighter than gold and is also much harder.

Gold is surprisingly soft and grades just 2 to 2.5 on the Mohs scale of mineral hardness, which is similar to a fingernail. Pyrite, which grades 6 to 6.5, is much harder but is very brittle.  

Strike a piece of gold with something heavy, and it will flatten. Do the same to pyrite, and it will break into many pieces.

Pyrite and gold have different crystal structures and a different coloured streak. Streak is the colour of a mineral in powdered form. In pyrite it's greenish black and in gold it's yellow.

The name 'Fool's Gold' is widely reported to have come about following the Great American Gold Rush because pieces of pyrite are said to have been mistaken for gold. Although the term may have been used during this event, its metaphorical use and the phrase 'fool's gold' go back much further.

This article, which you can read here, comes from a book about the mineral pyrite. It begins on page 6, which you can jump to from the contents page. I couldn't link to it directly. With this being a book, it takes a few minutes to download but makes an interesting read.

In films involving pirates, they would often be seen biting into a coin to confirm it was gold. This almost certainly came out of Hollywood. Biting into pure gold may leave teeth marks due to the mineral's softness, but biting a coin from this period would not have the same effect. This is because coins were already being alloyed with another metal to improve hardness.

Properties of Pyrite (geology)

Pyrite is an iron sulphide mineral, which means it's a chemical compound of iron and sulphur. It contains a high percentage of iron and is relatively common, hence can be found in many geological environments.

It occurs in a variety of forms, which makes it particularly popular with mineral collectors.

Pyrite crystals can be isometric (cube-shaped) which is one of the simplest and most common crystal shapes. They can also be octahedrons or pyritohedrons,(a pyritohedron).

Pyrite in a flat disc-like shape with outward radiating crystals is known as a pyrite sun. The crystal habit of pyrite can also be massive. 

Crystal faces can also be striated, which is another characteristic that distinguishes pyrite from gold.

In the late 1970s, deep-sea hydrothermal vents were discovered on the ocean floor at previously unexplored depths. These vents supported unique ecosystems with hundreds of newly discovered species. Many of the vents emitted mineral-rich fluids containing pyrite at temperatures as high as 400°C (752°F).

Gold and pyrite form under very similar geological conditions and can even occur together within the same rock. Inclusions of gold in pyrite are not uncommon.

Although pyrite could be used as an ore, it rarely is. That's because there are many other more suitable minerals from which gold can be extracted. 

Pyrite is relatively common and can be found worldwide, but generally only occurs in small quantities.

The Rio Tinto region of Spain has vast pyrite reserves. Countries including Bolivia, Brazil, Peru, Japan, Canada and Italy, to name just a few, have produced many fine specimens.

The Meaning of 'Pyrite'

The word 'pyrite' comes from the Greek 'pyr', meaning 'fire'. When struck with a hard stone or steel tiny pieces break away and react with oxygen to create burning hot sparks. This was one of the earliest methods used by humans to create fire.

The wheel-lock gun, developed around 1500, was ignited by spinning a spring-loaded steel wheel against a small piece of pyrite. This generated sparks, which ignited the gunpowder and the charge in the gun's barrel.

Pyrite Healing Properties

The healing properties of pyrite revolve around strength, protection and energy. It's widely used for shielding purposes because it blocks negative energy. It also prevents positive energy from escaping from the physical body and aura.

Pyrite strengthens confidence and masculinity and is said to be helpful for psychosomatic-related issues. Its energy stimulates enthusiasm, eases anxiety and helps combat frustration. Pyrite is a great crystal to have on your desk because it prevents a sluggish mood, combats fatigue, and energises the environment.

On a psychological level, pyrite boosts self-confidence and can help deal with an inferiority complex. It accelerates mental activity and improves memory and mental recall. Pyrite can be used in meditation to lessen the effects of a low mood and depression.

Article Pictures

Pictures 1 and 3 in our article were taken during visits to the Harvard Museum of Natural History and London's Natural History Museum.

Picture 2 is courtesy of Ron Wolf.  

Both images are clickable and redirect to the original photo.

Pop-up photos: Pyritohedron - Courtesy of Stan Celestian. Pyrite concretion - Courtesy of Ron Wolf.