Now here's a project for a bright young person intent on making a name for himself / herself. It would make a nice dissertation topic for an archaeology student. Title: The Colours of the Stonehenge Stones.
Get permission from EH to examine ALL of the standing and recumbent stones at Stonehenge. They are all numbered, so the task is a simple one. The whole job can be done in a day. Work out the protocols -- all stones to be examined in similar light and weather conditions, to avoid shadow effects, contrasts between wet and dry surfaces etc. Avoid areas heavily encrusted in lichens, and avoid fresh and broken faces. Take a standard colour chart, and record the colour of every single stone by matching as closely as possible to the colours on the chart.
Present data in table form and using wacky graphics. Publish results in prestigious journal. Win the eternal thanks of the academic community and live happily ever after.
Has nobody done this before? If not, why not?