Chemical weathering alters muscovite interlayers in ways that enhance the sorption of cesium (Cs) and rubidium (Rb) relative to potassium (K) at frayed edge sites. Gangue muscovite concentrated from kaolin ore has been shown to slowly sequester radiocesium, suggesting that natural Cs and Rb become enriched within interlayers that have experienced substantial K loss. In this study, alkali metals were shown to be released from weakened interlayers by mechanical delamination. Muscovite fractions (<45 µm and 45–90 µm) were leached with 35% HNO₃ to remove exchangeable ions, then partially delaminated by sonication for 30 minutes, followed by strong-acid extraction. Exchangeable and delamination-exposed K each represented only 1–2% of total K in the bulk material. The extraction techniques removed sorbed K, Cs, and Rb from sorbed and frayed sites in muscovite.