Lunar Seasonality in Precious Metal Prices
There is a body of research that demonstrates a slight but measurable effect on security prices according to phases of the moon. See here and here as examples. This short paper looks at the issue of these effects in precious metals.
The abstract states
We demonstrate for the first time the existence of a lunar cycle on precious metal returns. This appears to be more pronounced in silver than gold, with very little evidence for an effect in platinum
What is interesting (but which is not really brought out) is that the lunar effect on gold is as we would expect in a safe haven/ hedge asset.
The full citation is Lucey, Brian M. (2010), ‘Lunar Seasonality in Precious Metal Returns?’Applied Economics Letters, 17 (9), 835-38. and a downloadable version is available here