A series of sandstones which lie at the boundary of the Coal Measures with the underlying Marros Group in South Wales.
Origin
Said to have been coined by ironstone miners who once worked the siderite deposits which stratigraphically overlie this rock unit. Digging beyond this bed would yield no further iron ore and so, on reaching it, they could bid a farewell to further riches.
Modern English dictionary
Explore and search massive catalog of over 900,000 word meanings.
Word of the Day
Get a curated memorable word every day.
Challenge yourself
Level up your vocabulary by setting personal goals.