This commemorative 4 cent olive green block from the 1929 Yunnan provincial issue features the Grand Mausoleum built for Dr. Sun Yat-sen, the founding father of the Republic of China, and bears the overprint specific to Yunnan Province. Issued to mark the state burial of Dr. Sun, this design symbolizes national mourning and reverence for the revolutionary leader. The architectural depiction of the mausoleum reflects both the Neo-Classical design adopted for national symbols and the role of Sun as a unifying icon of the Republican era. Printed by gravure and line perforated 14, the stamps are ungummed, in accordance with the local printing norms of the time. This block includes a full vertical gutter and imprint margin with printer’s guide marks, highlighting its philatelic and production significance. It is listed in major catalogs as Michel CN-IM-YU 26, Scott CN-IM-YU 26, Yvert et Tellier CN-YU 26, Stanley Gibbons CN-IM-YU 26, and China Stamp Society CN-IM YN27. Condition: Mint never hinged block with full margins and corner selvage, slight paper irregularity in the lower right selvage. Estimate "$85 – 110".