Germany-DDR 1965 200 Years Mining Academy in Freiberg

• Label : "Deutsche Post" of the Geman Democratic Republic; 1965; commemorative stamps of the issue "200 years of the Mining Academy, Freiberg";
  

meant is the Freiberg University of Mining and Technology in Freiberg (Saxony) (German: "Bergakademie Freiberg")
(issue of 4 stamps )

Stamp datas:

• Catalogue numbers : Michel: No. 1142-1145; Yvert & Tellier: No. 842-845; Scott: No. 796-799
• Color : multicolored (black colors dominating)
• Watermark : none
• Nominal values : 10 – 15 – 20 – 25 (Pfennig)
• Postage validity : 11 November 1965 . 02 October 1990
• Designed by : Werner Klemke (1917-1994)
• Printed by : "Deutsche Wertpapierdruckerei", Leipzig
• Print process : Offset printing
• Perforation : Comb perforation, K 13 : 12½
• Print runs :

- 10 (Pfennig) : 5,000,000

- 15 (Pfennig) : 1,400,000

- 20 (Pfennig) : 5,000,000

- 25 (Pfennig) : 4,000,000

• Stamp size (printed area of a single stamp without signature line) : 39.0 x 20.5 mm

Commemorative stamps of the issue "200 years of the Mining Academy, Freiberg";
(issue of 4 stamps )

Stamps, mint

Michel No. 1142, mint	Michel No. 1143, mint
Michel No. 1144, mint	Michel No. 1145, mint

Stamps, postmarked

Michel No. 1142, postmarked	File:Germany-DDR 1965 200 Years Mining Academy in Freiberg 2a1a.jpg Michel No. 1143, postmarked
Michel No. 1144, postmarked	Michel No. 1145, postmarked

To the stamp morives:
- 10 (Pfennig) : Drift Oven (German: "Treibofen"), drawing after historical xylographics
- 15 (Pfennig) : Ore mining (German: "Erzgewinnung"), drawing after historical xylographics
- 20 (Pfennig) : Proustite (German: "Rubinblende" or "Rotgültigerz"), Ag₃[AsS₃]
- 25 (Pfennig) : Sulphur (German:Schwefel) in natural sterling form as pure crystalline structure