磨刀砂岩

Farewell \Fare"well`\, a.
Parting; valedictory; final; as, a farewell discourse; his
farewell bow.

Leans in his spear to take his farewell view.
--Tickell.

{Farewell rock} (Mining), the Millstone grit; -- so called
because no coal is found worth working below this stratum.
It is used for hearths of furnaces, having power to resist
intense heat. --Ure.