5 piece American Mokume Desk Set, circa 1910. Unknown American manufacturer, retailed by J.E. Caldwell & Co. Includes letter holder, frame (possibly calendar), stamp box, small tray, and letter opener with arrowhead handle. The envelope opener apparently unmarked, the small tray marked Sterling & Other Metals, others hallmarked and with applied retailer's plaque of JE Caldwell & Co. Hand wrought mixed metal and sterling mounts, silversmithing technique originating in Japan that was popularized in the US by Tiffany & Co. 
Weight: Approx. 4.5 lbs 
Measurements: Approx. Letter holder: 10 inches x 4.75 inches x 6.75 inches tall / Calendar: 5.75 inches x 2.75 inches x 5 inches tall / Box: 2.75 inches x 5.25 inches x 1.825 inches / Tray: 4.75 inches x 2.825 inches / Letter opener: 5.825 inches x 1.25 inches 
Condition: Letter opener appears to have a chip to the arrowhead, letter holder missing some rivets, please refer to photos.