Revision history for U.S. Geological Survey Fact Sheet 2026–3064 

Critical Minerals in Zinc Ore—An Update on Earth Mapping Resources Initiative Research in the Boulder Batholith Region, Montana

By Sean P. Gaynor, Eric D. Anderson, Kyle A. Eastman, Karen Lund, Chris Gammons, Heather Lowers, and Jay Thompson 

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First posted online March 4, 2026 
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Revised and reposted March 5, 2026, as version 1.1 

Figure 1 explanation label was revised from Cretaceous sedimentary rocks to Cretaceous intrusive rocks.