| So you're into sci fi? But what about sci fact?
Sometimes fact is stranger than fiction...
Each month our very own Voyager Science Queen* will bring you interesting,
quirky and downright bizarre tasty morsels from the world of science.
And its all completely, totally, 100% true!
October Sci-Facts
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Science Page October 2007
Colour My World
There are a lot of artists and illustrators who visit the Purple Zone, so I am dedicating this month’s page to them.
Pigment
Pigment is the basic substance that colours paint. There are natural and artificial pigments.
Blue Pigments
Ultramarine: a naturally occurring mineral of aluminium, sodium and sulphur (Lazurite and Lapis Lazuli). The mineral is ground into powder and mixed with a binding substance, such as wax or egg whites, oils, gums, or resins, to produce paint. It was used sparingly throughout history as it was often the most expensive paint to produce, and so it was most often used in religious paintings of the Virgin Mary. This is a deep, clear blue.
Prussian Blue: This is a modern colour, a compound of iron ferrocyanide. It is a dark blue, and it is prized as a ‘fast’ (non-fading) pigment.
Cobalt Blue: Cobalt is a hard, silvery metal. It is the metallic salt of cobalt that the pigment, known since the Middle Ages. Traditionally, cobalt have been has been used to give a rich blue to glass and ceramics. It is a beautiful deep blue, like deep water over white sand, but as paint it may appear greenish when mixed with yellow-toned oils like linseed oil.
Indigo: Indigo the pigment comes from a range of plants, like the indigo plant and the woad plant, and is one of the oldest pigments known to human beings. It has been used for millennium to dye fabrics. It is a blue so deep that it is nearly purple. It is often used in dyeing denim. This dye can also be produced by boiling certain Mediterranean shellfish...but why would you want to? Ewww....
Red and Yellow Pigments
Vermillion/Cinnabar: This is another mineral-based pigment; it contains mercury and so is toxic. As cinnabar is a rare mineral, historically this was another expensive pigment. It is a deep orange-red, used more in China and India as there were naturally occurring deposits of cinnabar in those countries.
Cadmium Red: Cadmium red is cadmium selenide. This colour has replaced vermillion as a fast red in modern times, though this is still a toxic substance. As well as cadmium red, there are cadmium yellow, cadmium orange and cadmium green.
Iron Oxides: These are the umbers, sienna and ochres of the palette. They are all earth tones, created by using clays as the base of the pigments. They range in tones from yellow to deep red.
Cochineal Red: The cochineal pigment is extracted from a scale insect that lived on cacti. It is a crimson or carmine colour, and was used mainly as a food colouring or in the cosmetics industry, though the Aztecs were known to use it as a fabric dye. It has been used to colour paints. In recent times, cochineal has been produced artificially, though the insects are still raised for their historic value.
Henna: Henna comes from tropical flowering plant. Against all expectations, the dark green paste made from the plant turns skin or hair or fabric a dark red-brown. It was very popular in the Eighties as a hair dye as it also conditioned the hair (I have the photos to prove it).
Saffron: As well as being a fragrant spice, saffron can also be used as a dye. Saffron comes from the stigmas of the saffron crocus, and so is very expensive to produce in any amount, and was used historically to dye the robes of royalty. It creates a yellow so dark as to be nearly orange.
This is not an exhaustive list of pigments. However, but I hope I have encouraged you all to go off and do research of your own.
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*The Voyager Science Queen is also
known as Lynne Green
So, who is this woman who attempts to entertain us with Science?
Well, I really am a scientist. I have a Bachelor of Science degree from the University of Queensland, in Zoology. And, at the moment, I am working in a Pathology laboratory.
I have always been intensely curious about every aspect of our universe, from the teeny tiny workings of the gene right up to the mind-bending forces that are twisting and knotting inside a blackhole. So, now I am sharing a brain stuffed full of trivia...and hopefully entertaining people at the same time.
As well, I write Fantasy stories and novels. One day, I hope to have a book published, but don't hold your breath. Reading is my other major love, and my favourite authors are Terry Pratchett and Isaac Asimov, though I could list hundreds of others. If I had one wish, I ask for more time to write!
Read previous Sci-Facts:
Lynne's Top Five Science Books
Animals at War
Busy Little Bees
Thinking Outside the Square
Water-Saving Tips
The Dark Side
Strange Objects
Updates: Bad New, Good News
Happy Holidays
Happy Birthday
Carnivorous Plants
What Makes Matter, Well Matter?
Putting the Science into Science Fiction
The Vortex
The Baddies on Your Bread
Scientific Updates on Previous Articles
Talking not Choking
Searching for the Lost Eden
A Comment on Comets
Mari Lwyd
The Pandemic
Zombie Insects and other oddities
You'll Be A Star!
Twisting
the Light
Green by name, green by nature
A No Science Page...
The Art of Statistics...
Ice, Ice, Baby...
Oddities
Bang, crash...Thud!
The Concept of Time
Fact versus Fantasy
Sci-Facts review
Incy-Wincy Teeny-Weeny Itty-Bitty Small Things
Flavour versus Flavonoids
The Third Eye
X Marks the Spot
The Horseshoe Crab
Pathology
The Tenth Planet
Science News Updates
The Sweet Keen Smell
Indulgence
Hollywood Crimes
Natural
Oddities
A Rainbow of Emotions
When is a star, not a star?
The Red Planet
Minerals
Hot Topic - Vitamins
A brief glimpse of New Technologies
Cuddly
Australian Animals
Something light-hearted
Living
in Interesting Times
New Hope
for Our New Year
The Meaning
of Life...
As the worm turns
Forensics
A Grab Bag of Facts
Bits and Bobs
Australian Achievements
Getting Your Attention
May Sci-Facts
After the Big Bang
The Big Bang
Ashes to
ashes; Dust to dust
Twists in
the tale
Robots in
the Swim and other things
The Tachyon
and other things
Looking for more scientific oddities? Have you checked out Dr
Steven Juan's website? He is, quite literally, the wizard of odds! |
