Tiger Iron and Tiger Eye share many common features.
Both are derived from sedimentary rock metamorphosis, both feature unique light refraction traits, and both are composed largely of quartz – but ultimately, they are two very different stones.
In this guide we will breakdown the characteristics and chemical composition of these two beautiful rocks to help you understand the similarities and differences between Tiger Eye and Tiger Iron.
Tiger Iron vs Tiger Eye (Explained)
What is Tiger Eye?
Tiger Eye, or Tiger’s Eye, is a semiprecious quartz prized for its striking chatoyancy, mesmerizing golden coloring and silky luster.
Chatoyancy is an optical phenomenon caused by light reflecting off microscopic mineral fibers and gets its name from the French word for cat, chat, a reference to the band of light reminiscent of a cat’s eye which moves across the stone surface.
The chemical composition and mineral classification of Tiger Eye sets it apart from other quartz varieties and reflects the uniqueness of this stone.
Tiger Eye is a metamorphic rock, meaning it was formed billions of years ago from the gradual transformation of existing stone by incredible heat and pressure within the earth’s mantle.
During this process, veins of crocidolite transformed into iron oxides which were gradually replaced and integrated with silicon dioxide, yielding the Tiger Eye quartz we know today.
These stones can be recognized by their beautiful honey colored sheen banded with rich brown, gold, and yellow hues.
They are opaque stones and reflect light in a bold band across the stone surface which moves as the stone is tilted.
Tiger Eye is rated between 6.5 and 7 on the Mohs hardness scale, has a specific gravity from 2.64 to 2.71, and a refractive index of 1.54 to 1.55.
Tiger Eye is a relatively common stone and is mined in several locations around the globe, most notably from mines in Australia, India, Brazil, and China.
It’s widely agreed that the best specimens come from the Griqualand West territory in central South Africa.
Interestingly, until these large deposits were discovered in South Africa, Tiger Eye was almost as valuable as gold.
Luckily for the mineral collectors among us, this isn’t the case anymore and good quality Tiger Eye can be purchased for just a few dollars nowadays.
Thanks to its durability, distinctive coloring, and fascinating chatoyancy Tiger Eye is commonly used as a decorative stone in jewelry and beads and several cultures associate this special stone with warding off evil spirits.
What is Tiger Iron?
Tiger Iron, also known as Tiger Eye-matrix, is a banded ironstone rock featuring Tiger Eye and stripes of hematite, red jasper, and quartz.
Inclusions of iron ore in the mineral matrix gives this stone its distinctive red coloring and lends itself to the name Tiger Iron.
The inclusion of red jasper and black hematite produce the striking bands of red and black which extend through the stone and allow Tiger Iron to be differentiated from Tiger Eye.
This collection of different minerals mean that Tiger Iron cannot be classified as a mineral in itself, but as a mineral matrix or aggregate metamorphic rock.
Tiger Iron registers between 5 and 7 on the Mohs hardness scale, has a specific gravity of 2.64 to 2.71, and a refractive index between 1.544 and 3.22.
Its colors include the bright gold of Tiger Eye interspersed with metallic grey, black, and brick red.
Where Tiger Eye is particularly highly concentrated the rock will exhibit chatoyance and flashes of light that dance across the surface.
Unlike Tiger Eye, Tiger Iron is mined only in small areas of South Africa and the Pilbara region of Western Australia.
Its seclusion to such limited areas of the globe is what drives up the price of quality Tiger Iron specimens when compared to the more common Tiger Eye.
Unsurprisingly, the unique colors and swirling patterns of Tiger Iron have solidified this rock as a favorite ornamental specimen.
The patterns of Tiger Iron are best observed when the stone has been smoothed and rounded off to allow the banding to become more visible.
It can be found fashioned into palm stones, beads, knife hilts, and jewelry as well as tumbled into pocket stones.
How are Tiger Eye and Tiger Iron similar?
Tiger Eye and Tiger Iron are both considered rocks, not minerals, due to their inclusion of several different mineral species.
Both stones were born from metamorphosis over billions of years and have a high iron ore content.
Both of these minerals feature characteristic chatoyance and distinctive banding of different minerals and their associated colors.
They are both opaque stones and can be polished to a bright, silky, luster.
They have very similar hardness and density ratings with only slightly different refractive indexes.
How are Tiger Eye and Tiger Iron different?
The difference between these two unique stones comes down to their composition and their source location.
Tiger Eye is predominantly formed from silicon dioxide with oxidized iron ore producing its golden colors.
By contrast, Tiger Iron contains silicon dioxide alongside variable levels of red jasper and hematite.
Although Tiger Eye can be found in several locations around the world, Tiger Iron is mined exclusively in South Africa and Western Australia – making it the more unusual of the two.
Why do people confuse Tiger Iron and Tiger Eye?
Tiger Eye and Tiger Iron can initially be easily confused thanks to their similar names and unusual light refraction patterns.
However, natural and untreated Tiger Eye will not contain the bright red and deep black featured in Tiger Iron and this comparative uniformity will usually generate stronger chatoyance across the stone surface.
These stones are as unique as they are complicated.
They can be easily confused by the untrained eye, but a better understanding of their composition can help in their identification.
A stone with a predominantly honey gold color and a strong light band refraction reveals itself to be Tiger Eye whereas a stone with red and black banding and less uniform light refraction is likely to be Tiger Iron.
You might also like: