Tonstein

{
  "id": "MLC-T-IND-006058",
  "term": "Tonstein",
  "field": "Industrial and trades",
  "definition": "A thin, distinct clay layer found within a coal seam, composed primarily of the mineral kaolinite. Formed from the alteration of volcanic ash that fell into ancient peat swamps, these layers serve as valuable stratigraphic markers for correlating coal beds across large basins. The presence of a tonstein provides a precise time-plane, aiding in geological mapping and resource estimation.",
  "subject": "Mining and extraction",
  "see_also": [
    "seat earth"
  ],
  "translations": {
    "de": "Tonstein",
    "es": "tonstein",
    "fr": "tonstein"
  },
  "url": "https://mlchart.com/terminology/industrial/tonstein/"
}