(Eastern Sierra) Silver Mountain, Cal., Cal., Aug 8 (Alpine), clear origin cds (ALP-230, R4) on 1868 cover to London, England, franked with 1861, 12¢ black canceled by cork handstamp, manuscript "Via overland to N.Y." routing endorsement, red "New York, Paid All, Aug 23" transit and red "London, Sp 7, 68" entry postmark, receiving backstamp, with original lengthy 3-page letter giving much information about many of the silver mines in the area and supplies a code for future letters, Very Fine. Scott No. 69  Estimate $750 - 1,000. $0 (Image)