Last Wednesday I attended a staff breakfast here at the BM – the topic was finding traces of an ancient paint, called Egyptian Blue, on the Parthenon Sculptures. The paint is not visible to the human eye any more, but can be seen as glowing white when using a technique known as infrared photography.
I’m not a specialist on this, but I will try to explain what I learnt. If there are mistakes then please do point them out!!
Basically, as I understand it, Egyptian Blue is a man-made pigment, used widely in antiquity, both chronologically and geographically. As luck would have it, one of the properties of Egyptian Blue is that it absorbs visible light, and emits infrared radiation. You can take a photo of the object using a filter, which blocks out visible light and only lets infrared through. This can be captured using a specialist camera, and, if there is Egyptian Blue present, it will show up as glowing white in an otherwise dull and grey photo.
Here is a link to a video they shot at the BM, a link explaining Egyptian Blue and a link explaining the method used. I think it’s really interesting, and I thought you might all be interested too, since Egyptian Blue was used in antiquity throughout the Mediterranean, Egypt, and in Mesopotamia.
The link I found I think might be a temporary one, as it is “latest news”…But I’m sure it will be archived on the site and we can always update this post with a new link later.