I am Calcitino, the little earth dwarf helper.
They call me Calcitino because my name is derived from my main ingredient, calcite.
I am what was needed in the past to make mankind smarter. You can also eat me to make yourself sound friendlier than you really are. Nevertheless, I usually react quite indignantly to sour.
In Germany, you can definitely find me in huge numbers in the north-east of Rügen. But I’m also often found on Usedom and a few Danish islands. The Flinthor usually hides inside me.
Incidentally, a system and two series in the Phanerozoic are also named after me.