Examples from the Web for glauconite
They may be seen occupying these shells, and when the shell is dissolved away perfect casts of glauconite are set free.
The sandstones are grey in colour, weathering buff or reddish-brown, tinged more or less green by grains of glauconite.The Geological Story of the Isle of Wight|J. Cecil Hughes
The green sand when weathered is brown or rusty coloured, the glauconite being oxidized to limonite.
Calcareous sands or impure limestones with glauconite are also by no means rare, an example being the well-known Kentish Rag.
Dark “green-sands,” very rich in glauconite, are followed by yellow sandstones with some flint.