History

Although nanotechnology is a fairly new science, the chief concepts have been developing over the course of fifty years. Interestingly, we have been employing nanotechnology for over a thousand years; from painting to making steel. Although, what has changed recently is our ability to manipulate and engineer in the nanometer scale.

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Medieval Stained Glass

One of the most documented examples of nanotechnology known in history is medieval stained glass artisans. They were the first nanotechnologists, as they, although unaware, trapped gold nanoparticles in the 'glass matrix' in order to generate the ruby red colour in the windows. They also trapped silver nanoparticles which gave it a deep yellow colour. As in today's finding it is the size of the metal (whether it be gold or silver) nanoparticles that define the variations in colour [Refer to Figure 1.1 for a chart of the different colours and according sizes].  This example of colour change is a testimony to the dramatic change in material properties at the nanoscale.

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Deruta ceramicists

‘Deruta ceramicists’ are another example of the practise of the early forms of nanotechnology. The people in Umbria, Italy during the Renaissance Period (1450-1600AD), used nanotechnology to produce iridescent or metallic glazes. They achieved these effects by using particles of copper and silver metal (between 5 and 100 billionth of a metre) particles in their glazes, this caused light to bounce off their surface at different wavelengths, thus giving it the ‘iridescent’ look. The Italians weren't the only people experimenting with nanotechnology in ceramics. More than a thousand years ago, the Chinese were known to use gold nanoparticles as an 'inorganic dye' to create a red colour in their ceramic porcelains.

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The Lycurgus Cup

The Lycurgus Cup was made by the Romans at around the fourth century (AD). An interesting factor about the cup is that the colours of the cup can change. When it is looked at in reflected light or daylight, it appears green. However, when light is shone into the cup and transmitted through the glass, it changes colour to red. What gives it these unusual optical properties is due to the glass containing tiny amounts of colloidal gold and silver. Colloidal gold is nanoparticles of pure gold suspended in water or a solution.



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Figure 1.1

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