Sometimes, after a certain time, secretions form from the brown calcareous earths. These are iron oxides, which form small nodules, or beans, and are therefore also called bean ore.
Bean ore, from which iron was smelted in the Middle Ages, is found in almost all limestone deposits. The red-brown color resembles coagulated blood (PBr 7).
Terra bruna di Otranto is suitable for Tempera, Watercolour, Cement / Tadelakt, Oil, Acrylics, Lime / Fresco.