March 23, 2012 Many living creatures build minerals into their
organism so perfectly as to produce structures with truly
astonishing properties. It is a combination of calcium carbonate
(CaCO3) and organic matter that makes the seashells, corallites
and sea urchin spines we find in our oceans. The brittlestar
Ophiocoma wendtii has developed the most perfect way of using
minerals for biological purposes. Related to the starfish, the
brittlestar long remained something of a mystery to zoologists
because it was clearly sensitive to light without having any
visible eyes. Then, a few years ago, scientists discovered that
the body of the reef-dwelling creature is covered with tiny
crystalline lenses made of calcium carbonate, which together
form a type of compound eye. Microlenses like these are used
technologically in all sorts of applications that require
optical systems and measurements in anything smaller than the
millimetre scale. For instance, they are used in
telecommunications to conduct light signals throu