Pink Sapphire and Pink Spinel are two aluminum oxide-based minerals famed for their stunning pink colors and sparkling brilliance.
To the untrained eye they can initially be difficult to tell apart, but closer inspection will reveal their distinctive crystal structures and characteristic light refraction patterns.
To make sure you can tell these pink gemstones apart – here is our guide on their particularities, their similarities, and their differences.
Pink Sapphire vs Pink Spinel (Explained)
What is Pink Sapphire?
Pink Sapphire is a member of the corundum mineral family and is composed of aluminum oxide with trace amounts of chromium.
As the chromium content of the crystal matrix increases, the stone takes on a deeper shade of pink which allows a wide variety of Pink Sapphire hues.
Sapphires can be found in many different colors, but pink is the rarest and is highly sought after in the gemstone business.
These beautiful gems can exhibit shades from a soft powder pink through to a shocking bubblegum pink with a glassy luster.
Physically, Pink Sapphires are a hard mineral registering a 9 on the Mohs scale with a specific gravity between 3.98 and 4.06, and a refractive index between 1.759 and 1.778.
Closer inspection will reveal a triagonal crystal structure and plenty of inclusions.
These inclusions produce asterism, a phenomenon which generates star-shaped refraction when under a strong light source.
The most valuable Pink Sapphires contain the most inclusions as better asterism produces more sparkly stones.
The majority of the world’s supply of Pink Sapphires are mined in Madagascar, Sri Lanka, and Tanzania with Kashmir producing the highest quality stones.
Sapphires have held cultural significance for thousands of years.
The Ancient Persians called Sapphires “gems of heaven” as they believed that the stones were taken from the pedestal that supported the Earth.
In later years, blue Sapphires became associated with divine favor as they formed the tablets upon which the Ten Commandments were inscribed.
Today, Pink Sapphires are increasingly popular in the jewelry industry where they are favored as a cheaper alternative to pink diamonds.
Their sparkly quality, vibrant pink coloring, and durability has solidified them as a staple in the world of decorative gemstones.
What is Pink Spinel?
Pink Spinel is a gemstone from the spinel mineral class and derives its name from the Latin word spinella, meaning spine – a reference to the naturally occurring points of a spinel gemstone.
Despite Pink Spinel’s beauty, until recent years it wasn’t particularly sought after in the gemstone industry due to both its rarity and its similarity to other, more common, pink gemstones.
Spinel is composed of magnesium aluminum oxide and can be found in a spectrum of different colors.
The color of Pink Spinel can range from a more delicate rose-pink through to a screaming hot pink with high color saturation and a natural brilliance.
Contributing to this excellent color is the lack of grey or brown subtones which can muddy the color of other gemstone varieties.
Pink Spinel registers an 8 on the Mohs hardness scale, has a specific gravity between 3.54 and 3.63, and a refractive index between 1.712 and 1.782.
The unique nature of Pink Spinel is revealed through closer examination of its crystal structure.
Like diamond, Pink Spinel has a cubic crystal structure and is singly refractive, determined by passing a bright light through the gemstone.
Pink Spinel is mostly sourced from the limestone plateau of Tanzania’s Ulanga District, but more mines have also been established in Madgascar, Sri Lanka, and Vietnam in recent years.
Although Pink Spinel has the spectacular coloring, durability, and clarity required of decorative gemstones, most specimens are contained in private mineral collections – a reflection of this stone’s rarity.
Interestingly, although Pink Spinel was first chemically differentiated from Ruby in 1783, it has been mistakenly incorporated into iconic pieces of jewelry including the UK’s Crown Jewels.
The famed ‘Timur Ruby’ and ‘Black Prince’s Ruby’ are both actually Spinel stones, although their names have never been changed to reflect this historical case of mistaken identity.
How are Pink Sapphire and Pink Spinel similar?
Chemically, Pink Sapphire and Pink Spinel are relatively similar.
Both are mostly composed of aluminum oxide, both have similar Mohs hardness ratings (9 and 8 respectively), and similar specific gravities (3.98 – 4.06 and 3.54 – 3.63 respectively).
Both gemstones are also prized for their bright coloring which spans from each end of the pink color spectrum, and they are mined in similar geographical locations.
However, initial looks may be deceiving as these gemstones have less in common than first meets the eye.
How are Pink Sapphire and Pink Spinel different?
Although they have a similar aluminum oxide backbone, these pink stones derive their coloring from different trace elements – chromium for Pink Sapphire and magnesium for Pink Spinel.
They also feature different crystal structures and refractive properties.
Pink Sapphire has a triagonal crystal structure, is doubly refractive, and is most valuable when the specimen contains many inclusions that give rise to its characteristic asterism.
In contrast, Pink Spinel has a cubic crystal structure and is singly refractive, hence its brilliance under strong lighting.
The best Pink Spinel specimens have high clarity and minimal inclusions both to the naked eye and under a microscope.
The treatment of these gemstones is also very different.
It is common practice for Pink Sapphire to undergo heat treatment to improve the stone’s colors and soften any purple tones.
Pink Spinel is rarely treated once it has been mined as the stone naturally possesses excellent clarity and color.
Why do people confuse Pink Sapphire and Pink Spinel?
Pink Sapphire and Pink Spinel have an overlapping color spectrum which may lead to confusion when differentiating between the gems based on color alone.
They are also found in geographically similar locations and were only chemically differentiated from each other relatively recently.
Pink Sapphire and Pink Spinel are undoubtedly the stars of the pink gemstone world and have legions of committed fans of both their beautiful jewelry and their value as collectible items.
If you are unsure of the identity of your gem specimen, examine it under a bright light and observe the stone’s refraction pattern.
For hundreds of years these two gemstones have been confused and mislabeled as each other, so take care to ensure you don’t fall into the same trap!
You might also like: