Guyana 1992 Anniversaries (Columbian Stamp Expo & Olympics) opt & surch in black $500 on $150 (150th Anniversary of Penny Black and Thurn & Taxis Postal Anniversary - Thurn & Taxis 6k stamp) unmounted mint
Guyana 1992 Anniversaries (Columbian Stamp Expo & Olympics) opt & surch in black $500 on $150 (150th Anniversary of Penny Black and Thurn & Taxis Postal Anniversary - Thurn & Taxis 6k stamp) unmounted mint