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Keywords from Image Description:
Nontronite. Two pieces of the chalky chartreusecolored clay mineral nontronite Nontronit Gre obere Probe unten Fundort Twin Buttes Mine Pima District Sierrita Mountains Pima County Arizona USA Beschreibung Zwei Stcke von kalkigem gelblichgrn gefrbtem Nontronit mindat org html mindat org html John Krygier John Krygier Nontronite