Lichen iridescence    


Iridescence caused by a layer of an unknown substance on these lichens. In each case, the first photo was taken with direct sunlight shining on the lichen, whereas I blocked the sun in the second picture. This way, only diffuse light would shine on the lichens, removing the iridescence effect.

2015-03-14 direct light || diffuse light.


2016-04-09 direct light || diffuse light.


2016-04-09 - a close-up of a part that was out of focus direct light || diffuse light.