Merchant's Exchange, San Francisco. Full bold strike of red oval handstamp on 1850 folded letter sheet to New York City, endorsed "Law's Steamer Columbus, 19 Oct" at top with "40" in circle rate handstamp; minor cover wrinkling and sealed tears at lower right, Very Fine, a rare early letter bag operator usage, pictured in Letters of Gold. Estimate  $1,500 - 2,000. $0 (Image)