The "Erivan" Collection of Western Postal History

large margins, tied by red "Paid" in double line oval (a style of device used by Wells, Fargo & Co.) to cover to Oroville, California, matching red "Langston's Pioneer Express Unionville" handstamp, on 3c Pink entire (U63) with printed black Wells Fargo frank, blue Wells Fargo Carson City handstamp on indicia, extremely fine and attractive, one of just six recorded covers with the rare Humboldt's Express adhesive, widely considered to be the most attractive local stamp ever produced, 2023 Philatelic Foundation certificate
This cover was carried by Langton's Humboldt Express from his office at Unionville to Carson City, where the connection to Oroville by Wells, Fargo & Co. was made.  Illustrated in Letters of Gold (p. 200). Ex Haas and Edwards Kuphal