The Colours of People

Everywhere you look, there are people. Different sizes, different shapes, different colours. And that’s pretty awesome.

But why do I have green eyes, my mum has blue and my dad has hazel?
Why is my hair a shade of browny blonde but my sisters is almost black?
And why oh why do I have to roast myself in the sun to get any form of tan that some people just have naturally??



All of the colour differences between people stems from pigments – any substance found within our cells which colours us in some sort of way.

It is the special kind of pigment, melanin which is to blame for any of your 3 major body colourings: eyes, hair & skin. 


Melanin is made within melanosomes which are found in cells called melanocytes.

Three important types of melanin include:

  1. Eumelanin = dark pigment 
  2. Phaeomelanin = light pigment 
  3. Neuromelanin = responsible for colouring regions of the brain – problems with neuromelanins are linked to Alzheimers and Parkinsons diseases.

The amount of these types of melanin we each get is determined genetically.




In our eyes, the melanin is found in the iris (the coloured part surrounding the pupil). The top layer of the iris is called the stroma and this is where those melanocytes are found.


More melanin will result in dark brown or black eyes. With over 55% of the world rocking them, brown eyes are the most popular eye colour.
Less melanin means blue, green or hazel eyes. Green eyes are the rarest in the world with approximately only 2% of the worlds population having them. 


In our skin, those melanocytes are commonly found in our deepest layer of skin, the basal layer. There are many factors which determine skin colour and it comes down to the size, distribution, shape and number of melanosomes plus how active the melanin within them is. It also takes into account the gene protein melanocortin 1 receptor (MC1R).

redheadMore MC1R activity = more eumelanin, less phaeomelanin. 

Some people have sort-of faulty MC1R genes and they are likely to have red hair, pale skin and freckles. 

Very simply, if you have high amounts of eumelanin but low amounts of phaeomelanin, the resulting skin will be black or brown. If you have low amounts of eumelanin but high amounts of phaeomelanin, the resulting skin will be light (freckles are likely too). People with very little levels (or none at all) of both eumelanin & phaeomelanin will have extremely light skin, this is known as albinism.

What about tanning? The more you expose skin to ultra-violet (UV) rays from the sun, the more melanin the skin produces. This will result in darkening the skin and helps to protect skin from any more damage. sun
Back in the day when most people huddled around the equator, they got a whole lot of sunlight and therefore a whole lot of vitamin D too (from the UV radiation).
We need vitamin D to help prevent illness such as rickets or soft bones so when people started moving away from the sun and dispersing to different, darker parts of the world, their bodies began to compensate for this loss of sunlight and the resulting loss of vitamin D. This happened by lower levels of melanin being produced and the lightening of skin, so more sunlight would be able to be absorbed. 


When it comes to hair, I barely know whether to describe mine as brown, blonde, muddy blonde, light brown? Sometimes I see strands of red and sometimes strands of black? It’s a bit of an identity crisis situation. 

You see, just like out skin, hair contains eumelanin (dark pigment) and phaeomelanin (light pigment). The density and the dispersal of the different types of melanin and their pigments will also contribute to differing hair colours, which can also happen across the space of one head. 

There is brown eumelanin and black eumelanin. 
If only a small amount of brown eumelanin is present, the resulting hair colour is blonde. Larger amounts of eumelanin will produce brown, dark brown and black hair. 
For red-heads, phaeomelanin is the dominant pigment which people with dark hair also sometimes produce. However, the darkness of their hair, thanks to eumelanin, overpowers the light pigment. In my case where I see hair strands that are red, light brown, and blonde, it is likely due to some phaeomelanin being produced. Grey hair is when only a small amount of melanin remains in the hair while white hair is the complete absence of melanin.


There are so many variables in our hair, skin and eye colours and that makes a pretty cool world full of unique and interesting humans. We’ve heard it before, but really, if we all looked the same, the world would be a pretty boring place! 


The building blocks of rocks

Today I want to talk about my first love, rocks.
I studied rocks for three years. I got to see rocks, hold rocks, scratch rocks, memorise rocks. Sometimes I got to go on field trips and look at really, really big rocks.

Rocks are pretty great.

What’s also pretty great are the building blocks of rocks, minerals. 
Minerals are the natural crystalline structures found within rocks, and are used to interpret what kind of rock you’re looking at e.g. garnet, topaz, diamond.  They are solid structures made up of chemical bonds and there are around 4000 different kinds identified so far. Although it’s not generally the best way to identify a mineral as most minerals are white in their purest form, the colours of minerals can also be pretty exciting and draw people in. 


We learnt about wavelengths waaay back here and it’s the amount of absorption of these wavelengths which determines the colour of a mineral.

It is mostly atomic bonds within these minerals which do all the wavelength-absorbing.

Minerals consist of elements. For example, an extremely common mineral, quartz, has chemical composition SiO2 meaning it is composed of elements silicon (Si) and oxygen (O) bonded together.


A few elements contain electrons that like to absorb wavelengths as it is these wavelengths which provide them with a booster of energy – the amount of energy depends on which wavelength is absorbed. Bonding between different elements changes the amount of energy electrons have resulting in different colours. elements

Elements that can do this can have great influence over the colour of a mineral, even just the tiniest trace. It is also thought that almost any element could produce almost any colour.

Nickel (Ni) for example will taint minerals green as seen in annabergite

Uranium (U) will colour minerals yellow like in zippeite

Cobalt (Co) creates the violet/red colour in erythrite

Diagnosing a rock over the colours of the minerals can be pretty inaccurate. A more reliable test is that of streak. Finding the streak, or ‘powder colour’ of a mineral involves rubbing the mineral across a white, unglazed porcelain plate. The colour of the powder left on the plate is the streak. Up to 20% of minerals have streaks that are super useful in determining what mineral they are.

We can also describe rocks as mafic or felsic.
Mafic is the term used for rocks and minerals with high iron and magnesium content and generally give rocks a dark colour.
Felsic is used for rocks and minerals with high silica content and are generally light coloured. 

I loved my rocksstudies of rocks as they seem to have a story. Once you learnt the tricks, you can start to decipher the mysteries of what has happened to that rock. 
Finding diamonds in a rock tell you that it has been buried over 150km deep as diamonds only form under extremely high pressure. 
Finding halite (rock salt) is a indication of evaporation of fluid, possibly old brine lakes or seas. 

Next time you’re walking along a beach, have a little squizz at the rocks you see. If you look really close, you might be able to see little shiny different-coloured crystals of all sorts of different minerals which could end up telling you a really good story. 


Karma karma karma chameleon

Today I watched an epic documentary about reptiles & amphibians. 
While watching said documentary, absorbing all the glorious David Attenborough narrations, all of the unbelievably epic shots and marvelling at a whole bunch of cold-blooded creatures, I saw the panther chameleon. 

Edging along a branch through the Madagascan forest, I was captivated. It’s pincer-like hands gripped around the branch as it crawled along, it’s individually rotating eyes looking 360° around itself. It looked so perfectly adapted to its environment, I was in awe. 

And then I realised.

Chameleons are colourful. 

My blog is about colours. 

I can write all about chameleons! 

I’m sure this will surprise you all when I say I’ve never really known a lot about chameleons or any sort of reptile for that matter, so we’ll be starting with the basics. 



  • A chameleon is a type of lizard, part of the suborder Iguania
  • With 171 different chameleon species, the majority of them are found in Madagascar 
  • The largest chameleons are over half a metre long (69.5cm)
  • The smallest chameleons can be only 16mm
  • The chameleon will continuously grow throughout it’s life
  • Chameleons eat insects and birds with an absolutely crazy tongue that can shoot out twice as far as its body length
  • They are 1 of only a small number of animals that can change the colour of their skin

Now this is where it gets interesting. It’s a common assumption that chameleons can just change their colour to match their surroundings. Scientists believed they changed colour in the same way that octopus or squid do by adjusting pigments in their skin cells to alter colours. 

However, it doesn’t work quite like that. 

Chameleons change the colour of their chameleoncellskin in response to their emotions or environmental factors like light or temperature. More recent research has discovered they do it by changing the actual structure of their uppermost layer of skin cells called iridophores. 

These iridophores contain nano-crystals (made up of guanine, one of the key components of DNA) which will determine the colour of Chameleons skin. 
When these nano-crystals are all close together, the chameleon is in a relaxed state. Because of this closeness, only small wavelengths such as blue or green are reflected from the cells and that is the colour we see the chameleon as. (To read about different wavelengths of colours click here).

When a chameleon gets amped up, say if a rival comes along, the chameleon will stretch his skin. This spreads these nano-crystals apart from each other and will consequently reflect colours of longer wavelengths such as yellow, orange and red

Beneath this fascinating upper layer of cells is another, thicker layer of skin cells. Scientists believe it is this secondary layer of cells which help to maintain the temperature of the chameleon as the cells found here reflect near-infrared sunlight. 

However, all this cool skin cell stuff going on, only really happens in male chameleons. Female and babies are generally dull colours as they don’t need to be competing with rival chameleons therefore their upper layer of iridophores is greatly reduced in comparison.

To conclude one of my favourite blogs to write so far, chameleons are pretty amazing creatures. For more interesting info on chameleons check out these resources:

The Happiest 5km Run

Three years ago, I participated in the first Colour Run in New Zealand.

The proof follows.


Also known as “The Happiest 5k”, you run/ walk/ skip/ jump/ crawl  your way around a track with periodically positioned stations of “colour” (powdered corn-starch) that gets thrown all over you. 

It truly is the happiest 5km run. You end up a walking rainbow, you’re not sweaty because you’re not really running, you’re rolling on the ground in coloured powder and you finish with a big smile on your face. Nothing could be better. 

So what were the reasons for creating such a fun run?

Apart from making some moolah of course, The Colour Runs – which are now found across the world from South America to United Arab Emirates – encourages people of any age and ability to be healthy AND happy. They even have a “Finish Festival” for everyone to dance it out and as stated on their website “release a few more endorphins”. 

You see, running or most workouts for that matter, encourage the release of endorphins. 

Endorphins = “any of a group of hormones secreted within the brain and nervous system and having a number of physiological functions. They are peptides which activate the body’s opiate receptors, causing an analgesic effect.” 

In other words… Endorphins are chemicals released from your brain which make you feel awesome, relaxed and take away pain. We like endorphins. 



Endorphins are neurotransmitters. This means they actually move through gaps in between neurons (cells in your nervous system) and help deliver messages from one neuron to the next. 

They then join up to opioid receptors which are found all throughout your body but most notably in the nervous system along with endorphins. There are at least 17 opioid receptors and the best known 3 are mu, kappa & delta.

This joining of endorphins and opioid receptors can ultimately stop other nasty molecules (tachykinins) from being released.  A special type of tachykinin called substance P is in charge of transmitting pain and involved in inflammatory body reactions – not what you want being released. 


Some people may experience an endorphin rush from eating chocolate or even if they talk to a stranger. It’s letting you know you’ve had enough, but that you should definitely come back to it again, because it made you feel good. 

The same happens in runners, endorphins (mimicked by drugs like morphine and heroine) give you a rush of pleasure that helps ease the pain of those rubbing blisters, the aching muscles, your tired legs. After your run, you feel awesome, experience “runners high” and decide you want to go for another run tomorrow because it made you feel so good and accomplished. 

Endorphins are the bodies natural way of feeling high and euphoric without the need for drugs. Drugs do give off the same feelings, but also come with a whole lot of other issues and much more baggage. 

No wonder The Colour Run leaves people wanting more. 

  1. You’re exercising (encouraging the release of endorphins)
  2. You’re interacting with people, many of whom are strangers (also likely encouraging the release of endorphins)
  3. You’re most likely with friends or family who generally speaking should be making you feel happy anyway
  4. You’re surrounded by colour, and as we saw in my last 2 blogs (here and here), colours can make you feel pretty darn great!


I’m a blue, what are you?

Although the scientific data is hard to come by, the psychology of colours is something that surrounds us. People have created businesses, websites, you name it based on these beliefs that colours either enhance or encourage certain emotions.

For some, the wavelengths of colours have been involved in connecting them to emotions.

As we know from Newton’s famous colour experiment, all of the different colours have different angles of refraction:

The angle formed by a refracted ray or wave and a line perpendicular to the refracting surface at the point of refraction.”


The colours also have different wavelengths:

“Light is measured by its wavelength (in nanometers). One wavelength equals the distance between two successive wave crests or troughs.”



The colour with the longest wavelength is red at around 665nm. This quality is said to therefore make it a powerful colour. 

Psychology wise, red:

  • Is said to increase your heart rate + blood pressure
  • Encourages positive feelings of warmth, excitement, love and passion
  • Also represents negative feelings of hate, violence and domination
  • In Chinese & Indian cultures red signifies good luck 

People with red personality type are said to be energetic, passionate people who love attention. They dream big and word hard tomakes those dreams a reality. Working the best with and around other people, red personalities are competitive and original.



The yellow wavelength is also long at around 600nm and creates an emotional stimulus. Yellow, like Goethe thought, is said to be the most psychologically strong colour.

Psychology wise, yellow:

  • Can stimulate mental processes and activate memory
  • Encourages positive feelings of joy, energy, inspiration and friendship
  • Also represents negative feelings of uncertainty, caution and fear
  • In Egyptian culture, yellow is symbolic of prosperity 

wavelength yellow
People with the yellow personality type are energetic and fun people to be around. They are extremely independent people who dream up big dreams but sometimes lack the focus to make these dreams real. Yellow personalities prefer a smaller group of friends and prefer mental tasks like puzzles to physical ones.



The wavelength of green is around 550nm, situating it in the centre of the spectrum. This gives green the colour of balance.

Psychology wise, green:

  • Is said to stimulate your pituitary gland and decrease allergy symptoms
  • Encourages positive feelings of freedom, generosity, youth and health
  • Also represents negative feelings of laziness, envy and frankness
  • In religions such as Hinduism and Buddhism, the heart chakra is represented as green


People with green personality type are thought to be the most sincere types of people. They are very open, honest and can see the bigger picture. With great manners and good-timing they can read people well and therefore have large social networks and are supportive, loyal friends to have.



The blue wavelength isn’t anything too special at around 470nm. However blue is the most liked colour across the world. 

Psychology wise, blue:

  • Is said to make food less appetising if eaten off a blue plate as well as lower blood pressure and the rate of your pulse
  • Encourages feelings of goodness, stability, loyalty, acceptance and cleanliness
  • Also represents negative feelings of despair, depression and isolation
  • Blue is the colour of the United Nations Flagwavelengthblue

People with the blue personality type are ultimately looking for peace. They very much value routine and familiarity but work extremely well as both an employee and employer. They enjoy having lots of friends and value both friends and family highly making them reliable and trustworthy people to have around.



The colour with the shortest wavelength is violet (purple) at around 400nm and it’s also the last visible wavelength before ultra-violet rays. This is said to create associations with time, space & the universe.

Psychology wise, purple:

  • Is calming and can increase feelings if spirituality and reduce anxiety
  • Encourages positive feelings of creativity, ambition, wisdom and luxury
  • Also represents negative feelings of grief, solitude, vanity and secrecy 
  • In Ancient cultures, purple represented wealth and in Catholicism purple is representative of Lent

People with purple personality type are generally more introverted people who are creative and like to dream. They like to be different from other people and are very giving people and like to see the best in everyone. Purple personalities are gentle and intuitive people. 

To delve more into what colour your personality is, you can take a test!
Just scroll on down and click on the big red “START TEST” button!

I got blue, what are you?


I admit, I am a sucker for finding information that can “match” my personality to colours, songs, breeds of puppies and celebrities, my star sign, you name it. 

However, I don’t truly believe that in spirit I am in fact a golden retriever nor do I need to define myself as a colour. 

This is a blog which investigates the psychological traits that are matched to colours as there is a MULTITUDE of resources out there which do it. It’s a bit of fun, it’s fascinating and there is a little bit of science to it! 

Do you see what I see?

Hello, hello. Welcome back to my wonderful world of colour.

Or in this case, perhaps not?

I just took this test here.

Luckily for me, I am part of the 94.5% of New Zealand‘s population that doesn’t exhibit signs of colour blindness.
I am one of the lucky 259 women who can identify a blue hue from a purple one, the 260th woman might see them both as blue. For men, colour blindness is much more common with 1 in 12. 

And when I say luck, for the majority of cases, being colour blind is almost a luck of the draw.

You see, colour blindness is a genetic mutation passed down from your parents.
The affected gene is carried on the X chromosome.
Women carry two X chromosomes (XX).
Men carry one X and one Y chromosome (XY).

You get one sex chromosome from your mum (it’s going to be an X, that’s all she has).
You get your second sex chromosome from your dad (it could be X, making you a girl orrrr it could be Y, making you a boy). 

The genetic family tree below shows the potential offspring of a non colour blind female who carries the mutated gene on one of her X chromosomes AND a non colour blind male.


Both X chromosomes must carry the affected gene for a girl to be colour blind meaning her father MUST be colour blind.  Only having one affected X chromosome will result in that girl being a carrier and she may or may not pass on that X affected X chromosome to her own children. 

Colour blind men can only pass on affected X chromosomes to their daughters, as boys get their Y chromosome from their father. 

Naturally speaking, nobody can determine whether you will be a boy or a girl.
Nobody can determine whether you get your mum’s dud X gene carrying the colour-blindness genetic mutation or you get her other one.
So the way I see it, it all comes down to luck.

As I mentioned in my last blog, two clever guys by the names of Thomas Young and Hermann von Helmholtz came up with the trichromatic theory of vision involving colour receptors. You can read all about it here. 


Our red, green & blue cone photoreceptors! 

At the back of the human eye, there are cone photoreceptors and rod photoreceptors. For the majority of cases, it is faults within the cone photoreceptor cells which lead to differences in the way a person might see colours.

Colours through normal vision (when all three cones are in good working order) generally look a little something like this….

However, have a browse through my table and have a look at how the different kinds of colour blindness affect the way in which these colours are seen. 


For people who are colour blind, some tasks in life can be made pretty tricky. This includes, but is not limited to, interpreting traffic light signals or coloured charts, or as simple a task as picking ripe fruit and veges at the supermarket. 

Unfortunately, there is no cure. However, it’s not all bad news. Modern technology advancements have contributed to helping out our colour blind pals. Apps have been created to help coordinate colours specifically for those trying to find an outfit that doesn’t clash. Some apps allow for a photo to be taken and all of the colours within that photo are then able to be identified with a simple tap of the finger. 

Also, technology in the optical world has now made colour-correcting glasses for people with red-green colour blindness that look exactly like any other pair of glasses. Which is pretty damn cool.

So next time you’re picking out those bananas at the supermarket and you can easily tell which ones are ripe and which are not, be grateful that you aren’t in that small, unlucky 5.5% of New Zealand’s population. 

Do you paint, print or photograph? Here are your primaries.

Hello again!

In my first post (which you can find here) we left off with genius man Sir Isaac Newton conducting a great experiment which made rainbows appear on his walls. colourwheel3-100

By doing this, he proved many great things! However, this experiment also led him to creating a colour wheel or a circular diagram showing how colours relate to one another – kind of like this one over here to the right. 

If we start at red on the left, we see the colour progresses to dark orange, light orange, yellow orange, yellow and so on from colour to colour – pretty self-explanatory right?

Well this is where we get to today’s topic – primary colours + their accompanying colour models. And we’re going to get started with some basics. 

Primary colours are most simply described as colours that need not be mixed with any other colour to be created. They are the purest forms of that hue. 
However (generally-speaking) you can mix primary colours to create any other colour you can dream of, which is a pretty great thing. 

In Newton’s prism experiment, he decided that the three primary colours were:
color wheel-100

  • Red
  • Yellow 
  • Blue 

This traditional trio of primary colours makes up the RYB colour model also known as the colour wheel model.


In between these primary colours on the wheel you’ll also find secondary colours. colourwheel4a-100These are hues which are made from the two closest primary colours to them in the wheel. 

For example:

  • Red + Yellow = Orange
  • Yellow + Blue = Green
  • Blue + Red = Purple (violet) 

The remaining 6 colours left on the wheel are tertiary colours and are made by mixing primary and secondary colours together, it’s as simple as that! 

colourwheeltert-100Since Newton’s discoveries, science has progressed in leaps and bounds, and as we learn more about light, it’s motion and how it interacts with surfaces like the human eye, the RYB model has become almost redundant. It is now really only used in the fine art world when mixing tangible pigmented paints. 

During these aforementioned leaps and bounds made by science, it was found that red, yellow and blue were not in fact the best colours to combine when it came to presenting media through electronic systems using light e.g. TV, computer screens or photography.

In fact, red, blue and green are known as light primaries and combine in different intensities to around 216 different colours suitable for use through electronic screens. This combination creates the RGB colour model.

The RGB model is also known as the additive model. This name refers to the addition of different intensities of red, green and blue superimposed (overlaid on each other). The colour seen is dependant on the intensity of each colour. Complete intensity will result in white (as seen in the middle of the diagram) whereas no intensity will result in black.


This colour model has been important since long before the explosion of technology. In the 1800’s, two scientists Thomas Young and Hermann von Helmholtz came up with the Trichromatic theory – that the way in which humans see colours is based on ‘colour receptors’ in our eyes – more specifically red, blue and green receptors. 

It was only these three receptors that were needed to see any and all colours on the spectrum. They thought that when each receptor was active, you would see the respective colour. If two were active at the same time – say your green and red receptors were active, you would be seeing a yellow hue. To see white, all three receptors would be stimulated equally. 

The Young – Helmholtz theory is still valid today explaining the aspect of colour vision associated with receptors.  

Quite literally the opposite, the subtractive model is also known as the CMYK model – the third and final colour model we’ll be looking at today. It involves cyan (a funny word for bright, light blue), magenta (a funny word for bright pink), yellow and black, called pigment primaries and it is mostly used in the printing world with inks and dyes. cmykmodel

As we saw at the end of my first blog, white light is made up of all the colours in the spectrum. In the CMYK model, white light is reflected off of a surface that has varying amounts of cyan, magenta and yellow inks upon it (the amounts are dependant on the colour aiming to be produced). The inks interfere with the white light, more or less ‘break it up’ and therefore the light that gets reflected back, is seen as a colour. 

On a piece of paper fresh out of the printer, the three colours are arranged in little dot patterns called rosettes that the human eye can’t make out unless looked at extremely closely. The CMYK colour model can actually produce many, many more colours than the RBG model because of this patterning.



So next time you go to fill up those (ridiculously expensive) printer inks yet again, or are about to paint the next Mona Lisa, or maybe just as you’re reading this blog and looking at all the pretty colours, think about these models, the clever people that created them, and how cool the world really is in colour.