早くも正解者でました。詳細は以下の通り。
Rosiclare Level, Cross-Cut Orebody, Minerva Mine Cave-in-Rock, Illinois. Mined October 1990.

ということで産地クイズは終了。おつきあいありがとうございました。
皆様、あとはいけやま問題をお楽しみください。

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Dear friends, your presence is requested in Chicago, Illinois, to assist in the extirpation of… https://t.co/3A0NVzcpyU

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Find your place in the sun at the Art Institute, where admission is FREE for Illinois residents, Monday through Friday, as part of Free Winter Weekdays—now through February 15.

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Meet Violet and Donna, the two main characters in Everjoy, Illinois!

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New artwork for sale! - "Chicago Illinois Skyline" - https://t.co/r9i7bxbQux

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Explore Rodin’s incomparable ability to bring bronze and stone to life in the exhibition "Rodin: Sculptor and Storyteller.”

Illinois families enjoy FREE museum admission during Free Winter Weekdays—now through February 15.

LEARN MORE—https://t.co/loAjf2AaC5

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Now Sold. Winter Melt. On its way to Bloomington Illinois!

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Virginia Frances Sterrett (1900-1931) was born in Chicago, Illinois, in 1900. She was an introverted child who preferred the world of imagination and drawing to social interaction with other children at school.

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Johnny Gruelle was born 137 years ago today in Arcola, Illinois, author, illustrator, created Raggedy Ann and Raggedy Andy
https://t.co/k3Q8Ivm6Kf

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