Details:

• January 28, 1864 (Julian) a letter dated January 25 posted at St. Petersburg by Gustave Sterky & Fils acknowledging a payment from C.J. van Opstall. Sender wrote 'Porto' in upper right corner. At the post office restated by hand stamp 'PORTO' (unpaid). The circular postmark 'St. PETERSBURG * VII. EXP. / 28 JAN 1864' was applied backside.

Dobin: 02.02 type 01a. Applied by the office for accepting and dispatch of foreign correspondence, postmark was used between 1859-1866, Rarity 1.^[1]

• Red 'Aus Russland' applied. Mark used as a German entry/transit mark aboard the Konigsberg-Bromberg T.P.O.

White: Aus Russland type RY3

• Black 'KÖNIGSBERG Pr 10 2 II BROMBERG' mark applied at reverse.
• Prussian accountancy mark 'P.33.'(PRUSSIA) with article allowing Prussia 77.5 centimes per 15 grams of mail. Single rate was 11 decides due.
• February 12, blue 'PRUSSE ERQUELINES 12 FEVR 64 3'. French entry mark at Erquelines. 3's show the postmark was struck at Paris. Rate was assessed at double weight: 22 decimes, and mediaeval manuscript '22' applied.
• February 13, 'PARIS 13 FEVR 64 (60)' transit mark at reverse.
• February 13, 'BORDEAUX 13 FEVR 64 (32)' receiver at reverse.