Glauconite
Spherical aggregates of
calcite
with embedded glauconite sand grains
Origin: Road workings, Green County, Wisconsin, USA
Sample size: 4 x 5.5 cm
Layered clay deposits with several layers containing the green glauconite
clay
Origin: Claypit De vlijt, Winterswijk, The Netherlands
Sample size: about 2.5 x 2.5 cm
Balls of sandstone to over 1 cm in diameter. The entire specimen is green due
to inclusions of micro glauconite.
A sandstone matrix concretion forming balls to 3 cm in size, intergrown and
coloured green by micro inclusions of glauconite.
Origin: near Juda, Green County, Wisconsin, U.S.A.
Sample size: 5 x 3.5 x 11 cm (top), 11.5 x 7 x 5 cm (2nd row), 10.8 x 8 x 3.1
cm (3rd/4th row), 7.5 x 9.2 x 3.5 cm (bottom)