Glendonite primarily forms in cold marine sediments, particularly in regions that have experienced glacial or permafrost conditions in the past. It is commonly associated with geological periods characterized by colder climates, such as the Paleocene-Eocene Thermal Maximum (PETM). Glendonite fossils are often found in sedimentary rocks, particularly in marine shales and mudstones.
 
The curved or coiled shape of glendonite is believed to result from the expansion of ikaite crystals as they transform into calcite due to changes in temperature or pressure. This expansion causes the crystals to bend or twist, resulting in the unique glendonite morphology.
 
As a fossilized form of calcite, glendonite is primarily valued for its scientific and paleontological significance. Its presence in rocks can provide valuable clues about past climate conditions and environmental changes. Glendonite fossils are also sought after by collectors due to their unusual and aesthetically appealing shapes.