Is primal still used?
Despite the extensive mining of bog iron, the ferrous rock can again be found frequently in Dutch soil, since the formation of primal banks only lasts a few decades.
As far as is known, no more iron is extracted in the Netherlands for the production of iron. It is therefore not clear why primordial soil was excavated between Zwolle and Meppel, which the questioner has established. However, primal is still used in very different applications.
Many farmers still sprinkle some iron in the pens of young piglets to prevent ‘white shoots’ (diarrhoea). A former butcher reported that he liked to buy beef cattle from the iron-rich soils along the Runde because of the good slaughter weight and the quality of the meat.
The dairy in Eexterveen was the only one in Drenthe that did not have to use a butter dye because the dairy cattle graze almost exclusively on iron-rich soils. About fifty years ago, in the vicinity of Meppel, the children were quietly put to bed when there was a threat of thunderstorms, because ‘the showers don’t cover the Reest, because that’s ‘primarily in the ground’. And at Garminge lightning always struck a certain iron-rich meadow during thunderstorms; that stopped after the construction of a high-voltage power line. When this pipeline was removed in 1981, it was rife again after that.