The Butterfly Effect

 

 

COLOUR AND VISION & THE NATURAL HISTORY MUSEUM

"Through The Eyes of Nature"

 

The Natural History Museum's new exhibition, "Colour & Vision" features many wonders of nature. To demonstrate how colour is often a warning they use the cinnabar moth as an example:

 

"Orange stripes, red spots and black mouths are all warning signs that an animal is dangerous. Poisonous and venomous animals often warn off potential predators with dramatic colours and markings." Colour and Vision

 A display of Cinnabar moths at the Natural History Museum's new exhibition "Colour & Vision"

A display of Cinnabar moths at the Natural History Museum's new exhibition "Colour & Vision"

I first encountered a cinnabar moth when I was on my way to the studio in Manchester a few years ago. The bold black and red patterns of the little winged insect caught my eye so I took a photo of it and looked it up. The patterns are so striking it had a real impression on me. I wanted to try and capture it in a ring, so it really a "Moth Effect" rather than a "Butterfly Effect"!

 The patterns of the wings of the Cinnabar Moth inspired this red and black ring

The patterns of the wings of the Cinnabar Moth inspired this red and black ring

 Image of Cinnabar Moth courtesy of Charles J. Sharp Photography

Image of Cinnabar Moth courtesy of Charles J. Sharp Photography

 

The larvae of the cinnabar moth eats the leaves of the ragwort plant making themselves and the adult moths they become poisonous. The red colour warns predators not to eat them as doing so could be fatal.

 

Red = DANGER

 

The cinnabar moth is actually named after the bright red mineral cinnabar, which is also poisonous.

A form or mercury sulfide, this mineral is highly toxic.

 The mineral Cinnabar, used for making vivid red pigment

The mineral Cinnabar, used for making vivid red pigment

When ground it is used to create the pigment "Vermillion". Treasured for its vivid hue, it is the only red pigment that was known to the ancients. Vermillion was revered by the ancient Romans. They even used it to paint the faces of their victorious commanders during the "Roman Triumph" Ceremony.

Because pure cinnabar was so rare, vermillion became immensely expensive and the price had to be fixed by the Roman government at 70 sesterces per pound - ten times the price of red ochre.

 The figure is a lady harpist, painted in vivid pigments by the Ancient Romans and recently found in Arles.

The figure is a lady harpist, painted in vivid pigments by the Ancient Romans and recently found in Arles.

The image above shows a fragment of Ancient Roman Fresco recently unearthed in Southern France, the colours still vivid after spending 2000 years buried in the dark. The use of the expensive red pigment shows how wealthy the inhabitants of the villa were.

You can read more about the history of this red pigment with Windsor & Newton's "Spotlight on Vermillion".

 

Unlocking the Mysterious Mineral Box

 

Museum Minerals

 

I recently met with Robin Hansen, a curator at the Natural History Museum in the Minerals division for a sneak peek of some of the minerals going into a new exhibition.

 

Robin is an award winning gemmologist, previously working with private collectors. I really valued Robin's expertise to unlock some of the secrets behind how these amazing specimens form. 

One in particular really fascinated me, it was large and matt with cube shaped hollows all over the surface this was an Epimorph.

 

 
  Quartz Epimorph    Image from Crystal Classics: "specimen shows cubic edged impressions of pre-existing probable Fluorite crystals measuring to 3.5 on edge"

Quartz Epimorph

Image from Crystal Classics: "specimen shows cubic edged impressions of pre-existing probable Fluorite crystals measuring to 3.5 on edge"

  Example of cube shaped Fluorite    Image reproduced from the 'Mineral Images Gallery' of the Mineralogical Society of Great Britain & Ireland (www.minersoc.org")

Example of cube shaped Fluorite

Image reproduced from the 'Mineral Images Gallery' of the Mineralogical Society of Great Britain & Ireland (www.minersoc.org")

 

 

Epimorph:

A HOLLOW CAST LEFT BY A MINERAL THAT HAD GROWN OVER AN INITIAL MINERAL WHICH HAS DISSOLVED AWAY.

 

 

 

 

There would have originally been a specimen of fluorite, formed from crisp angular cubes which this other mineral had grown around.

 

There is a beautiful and intriguing example of an Epimorph currently on display in “The Vault” at the Natural History Museum.

 

The mystery of this particular example is that the original inner mineral should have dissolved before the outer box, so we're not sure exactly what caused this epimorph to form.

 

What is particularly beautiful is how another mineral has started to grow inside the cavity left behind.

 
  Box epimorph of siderite after fluorite from the Virtuous Lady mine in Devon. Image courtesy of Jolyon & Katya Ralph from www.Mindat.org

Box epimorph of siderite after fluorite from the Virtuous Lady mine in Devon. Image courtesy of Jolyon & Katya Ralph from www.Mindat.org

So now, to investigate this amazing process further and how it links to jewellery see my next post coming up where I visited Glyndwr University’s jewellery and metalwork department the same week for a demo on Investment Casting.