Mordenite from Rat's Nest Claim, Idaho, USA

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Lustrous very light pinkish gemmy crystals of heulandite to 2.0 cm in size across the top of a matrix with white silky crystalline mordenite. This is in very good condition. The specimen comes with a previous label from the collection of Ray DeMark.Located near Challis in Custer County, Idaho, USA, the Rat's Nest Claim is a world-famous mineral locality situated within Eocene-age Challis Volcanic Group rocks, where hydrothermal solutions altered vesicular basalt and cavity-rich volcanic tuff. Discovered by collector Lanny Ream and later heavily worked by miner John Cornish, the claim became renowned among mineral collectors in the late 20th and early 21st centuries for producing some of the finest known specimens of heulandite. A member of the zeolite group, heulandite at this site commonly forms vibrant orange-to-pink, highly lustrous, coffin-shaped crystals often perched on matrix lined with white mordenite, making these specimens globally prized for their aesthetics and fluorescent properties.