Coin sample of 1778 (with portrait of Catherine II in adulthood). Produced in 1778-1779, and 1781 in the years 1783-1793. In a circle the front and back of a rim with notches (on some coins may partially be absent, it is not a marriage).
On the obverse is a portrait of Catherine II in profile, face to the right. Under the portrait letters "СПБ"(Saint-Petersburg). In a circle the inscription - "Б•М•ЕКАТЕРИНА•II•IМП•ИСАМОД•ВСЕРОС"(stands for "the grace of God Catherine II Empress and autocrat of all Russias").
The reverse depicts a simplified coat of arms
of the Russian Empire of second half XVIII century: the double-headed eagle with the lifted wings, crowned by two Imperial crowns, above the same crown but larger. Right Talon the eagle holds a scepter, the left power. On the eagle's breast shield with an indication of the par value - the number "20". Below in a semicircle is a ribbon with the year of issue "1784". On the sides and at the top there are 20 raised dots (the number indicates the nominal).
Photo from the site:
staraya-moneta.ruVarieties of the 20 cents of the sample of 1778:
Portrait with long neck: 1779 (St. PETERSBURG);
1778, 1781 (St. PETERSBURG, inscription "ВСЕРОСС."on the obverse);
1778, 1781 (St. PETERSBURG, inscription "ВСЕРОС."on the obverse);
Portrait with a short neck: 1783-1793 (SPB).