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Northamerica/USA/ Lake Superior Agates |
These agates are spread by glacial forces over the middle north of the United staates and are belonging to the oldest agates in the world. They are having their origin in the 1.2 billion year old Great-Rift-Lavaflows.
Agate collectors are able to find them near to their place of origin in Minnesota,Wisconsin and Michigan. In Iowa, Illinois, Nebraska, Kansas and Missouri they can be found too.
Agate-nodules of this type can be found in gravel-pits or fields.
They show red to brown colours and sometimes a strong “shadow-effect” - caused by their fine banding. Besides the common fortification banding lakers can present the “Uruguay-type-banding”.
Deformations in banding can produce interesting patterns.
In the early days of collecting theses agates they were cut and polished (or even thumbled) - unless if they had a very fine natural pattern on the outside of the nodule. Today the collectors are prefering agates with a perfect natural shape and untreated pattern.
