Add to ORKGPyrite-Quite recently there have been obtained from limestone cavities in Lee County some small but very perfect pyrite crystals. The faces are brightly reflecting and meet in sharply defined edges. The more common crystallographic forms are the pentagonal dodecahedron, or pyritohedron, and the cube, with all gradations between the two. Though small they are perhaps the most perfect crystals of this mineral found in the state up to the present time
Despite the circumstance that in the Iowa part of the Great Plains, lying between the Mississippi Ri...
In his report on the geology of Lee county Keyes described a fine-grained, compact limestone at the ...
Throughout the drift mantled surface of Iowa, glaciated boulders of crystalline rocks are of common ...
Pyrite-Quite recently there have been obtained from limestone cavities in Lee County some small but ...
Within the limits of Webster County are found a number of interesting minerals. The following notes ...
Dolomitic limestones of the Middle Devonian Cedar Valley Formation are exposed at Pint\u27s Quarry. ...
As a terranal name Lake Valley is applied to a remarkable blue limestone occurring at the famous sil...
In the extreme north western corner of Iowa there is a small area of very hard, thoroughly vitreous ...
At various places in the Archaean areas of Missouri the granites and porphyries are cut by dikes of ...
The geological location of the Ledges in the state, the kinds of rock found there and their arrangem...
It is a fact almost too well known to state here that the most important single problem in earth-stu...
The enthusiastic collector of rocks and minerals enjoys and practices a most interesting hobby. Natu...
On the general geological map of Iowa there are three peculiarities in the areal distribution of the...
Except they be trained geologists few Iowans there are who would ordinarily think of looking for mou...
The surface of Iowa, and of the neighboring states north and east as well, is strewn with boulders o...
Despite the circumstance that in the Iowa part of the Great Plains, lying between the Mississippi Ri...
In his report on the geology of Lee county Keyes described a fine-grained, compact limestone at the ...
Throughout the drift mantled surface of Iowa, glaciated boulders of crystalline rocks are of common ...
Pyrite-Quite recently there have been obtained from limestone cavities in Lee County some small but ...
Within the limits of Webster County are found a number of interesting minerals. The following notes ...
Dolomitic limestones of the Middle Devonian Cedar Valley Formation are exposed at Pint\u27s Quarry. ...
As a terranal name Lake Valley is applied to a remarkable blue limestone occurring at the famous sil...
In the extreme north western corner of Iowa there is a small area of very hard, thoroughly vitreous ...
At various places in the Archaean areas of Missouri the granites and porphyries are cut by dikes of ...
The geological location of the Ledges in the state, the kinds of rock found there and their arrangem...
It is a fact almost too well known to state here that the most important single problem in earth-stu...
The enthusiastic collector of rocks and minerals enjoys and practices a most interesting hobby. Natu...
On the general geological map of Iowa there are three peculiarities in the areal distribution of the...
Except they be trained geologists few Iowans there are who would ordinarily think of looking for mou...
The surface of Iowa, and of the neighboring states north and east as well, is strewn with boulders o...
Despite the circumstance that in the Iowa part of the Great Plains, lying between the Mississippi Ri...
In his report on the geology of Lee county Keyes described a fine-grained, compact limestone at the ...
Throughout the drift mantled surface of Iowa, glaciated boulders of crystalline rocks are of common ...