ELISABETH I. - Elisabet imperatriza wseros sinskaja petra welikago dscherj (rossice). Elisabetha imperatrix. Omnium Russiarum Petri. Magni. Filia.

Extremely rare half portrait print of Elizaveta Petrovna (29 December [O.S. 18 December] 1709 – 5 January 1762 [O.S. 25 December 1761] ), also known as Yelisavet and Elizabeth, she was the second-oldest surviving daughter of Peter the Great and Catherine I of Russia. She was the Empress of Russia (1741–1762) who took the country into the War of Austrian Succession (1740–1748) and the Seven Years' War (1756–1763).
On the eve of her death in 1762, the Russian empire spanned almost 4 billion acres (more than 16 million square kilometers).

Johann Stenglin was a well known engraver, born at Augsburg in 1715, he studied under Bodenehr, and engraved after Dinglinger, Grooth, Haid, Klein, and De Meytens. In 1743 he received a summons to St. Petersburg, and engraved portraits of Russian Czars and members of the Royal Family. He died at St. Petersburg in 1770.
Mezzotint was the first tonal method to be used, enabling half-tones to be produced without using line- or dot-based techniques like hatching, cross-hatching or stipple. Mezzotint achieves tonality by roughening the plate with thousands of little dots made by a metal tool with small teeth, called a "rocker." In printing, the tiny pits in the plate hold the ink when the face of the plate is wiped clean. A high level of quality and richness in the print can be achieved.
The process was especially widely used in England from the mid-eighteenth century, to reproduce portraits and other paintings.
Mezzotints produced in Russia are very rare.

Reference: Rovinskij II, N 7. Nagler XIX, 415, 2.