Industry, sector and description for Universal Display. Universal Display researches, develops, and sells organic light emitting diode (OLED) technologies and materials for the flat-panel display industry.
The first requirement for all master horizons other than O horizons is that they are composed mostly of mineral material. It is very important to be able to differentiate organic from mineral material. Dark color of the A horizon is due to the mixing of humus with mineral.
A horizon will be either an E horizon, usually not present in grassland/ agricultural soils, or a B horizon, the horizon of accumulation. Material from the A (or E) horizon, such as clay and carbonates, leach downward and accumulate in the B horizon. The C horizon represents the weathered parent material. Bedrock (designated by R) or a deep accumulation of materials deposited by wind, water, glaciers or gravity often lies below the C horizon.