They remembered a million useless things, a quarrel with a workmate, a hunt for a lost bicycle pump, the expression on a long-dead sister’s face, the swirls of dust on a windy morning seventy years ago: but all the relevant facts were outside the range of their vision. They were like the ant, which can see small objects but not large ones. And when memory failed and written records were falsified — when that happened, the claim of the Party to have improved the conditions of human life had got to be accepted, because there did not exist, and never again could exist, any standard against which it could be tested.
George Orwell, Nineteen Eighty-Four
- Shale (Wikipedia)
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2Si2O5(OH)4) and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite. Shale is characterized by its tendency to split into thin layers (laminae) less than one centimeter in thickness. This property is called fissility. Shale is the most common sedimentary rock.