Greensand

The numerous beds of coarse Oolites, which in England in general occur below the lyas and greensand, are entirely wanting in Ireland: But this is the case also in the neighbourhood of Lime-Regis in Dorsetshire, which place affords an exact counterpart of the Irish series here described.

Source: wiktionary

The Sassafras soils occur on the Atlantic coastal plain from the mouth of Chesapeake Bay to Long Island. They are developed from coastal-plain materials consisting of sand and clay, free from lime carbonates or greensand.

Source: wiktionary

Glauconite occurs as granules which may be mixed in all proportions with ordinary sand. Some greensands contain over fifty percent glauconite. The glauconite may be concentrated in certain laminations or scattered throughout the sand. If abundant enough, it imparts a speckled appearance to the rock.

Source: wiktionary

Some filtering materials are used for special purposes rather than general use. One such material is greensand, sometimes referred to as "manganese greensand." […] [M]anganese greensand is produced when greensand (the mineral glauconite, a natural zeolite) is treated with manganous sulfate followed by potassium permanganate. This process forms a manganese-coated greensand, which can remove soluble iron and manganese. When the removal capacity of the manganese greensand is exhausted, it can be restored by soaking the filter bed in potassium permanganate. In many water treatment plants, potassium permanganate is continuously fed into the influent water, so the manganese greensand can be continuously regenerated.

Source: wiktionary