Dalmanitids

Pictured below is a very nice, large Dalmanites cephalon. A collections manager from the Field Museum brought it to a Chicago Rocks & Minerals Society meeting last year. The label says it's from the collection of Rollin Thomas Chamberlin, (1881-1948) professor of geology, University of Chicago. It was found at McCook Quarry, which unfortunately, is not accessible to collectors these days.


Luckily, there are still a few localities to find Dalmanites in the Chicago area. To find one complete is extremely rare, but their disarticulated cephali and pygidia remains can be found with some luck and  persistence. Here are a few I have found.


Had to glue eye back on.



Below is a larger one measures about 4cm across, Glyptambon verrucosus, though not as exquisite as Mr. Chamberlin's specimen. This is how I found it after splitting open the rock. Dolostone can be tricky to work with, but with trial and error, and some luck, it can be rewarding. Had to glue it back together and patch up a couple areas with glue mixed with crushed dolomite.





It might be difficult to see in the photograph, but each individual lense of the schizochroal eyes are remarkably preserved.


And here is a little one found just after first snow, early winter. Measures about one centimeter, unfortunately both eyes lost.



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