The Amazonian Lillies at the Botanic Gardens, Adelaide, shot on black and white film.

I'm fascinated by the colour silver. I asked scientist Ian Gibbins to descibe silver. I asked "Is it a colour?" His response: "Not really ... it's a type of reflective surface, that can take on colours depending on the ambient light and the nature of the surface itself. So pure silver is actually more or less white, which means that it reflects all the wavelengths of visible light in pretty much the same proportions. The silvery-ness is due to the fine structure of the surface which means that not all the light is reflected in the same direction.

Gold is "coloured" because is absorbs most wavelengths in the spectrum except for the yellowish ones (I can't remember the exact wavelengths!!). If you beat gold out to thin gold leaf, you can see through it / shine a light through it... and it's green, which is a consequence of the complex interaction between the wavelengths being reflected (yellow) and those being absorbed by the thin gold (red and blue)."