You are looking at a SILVER medal for the war of 1853-1856. The medal was first instituted on August 26, 1856 during the reign of Tsar Alexander II to commemorate the War of 1853-1856 and was officially known under the name of "Medal for the Eastern War".
The obverse of the SILVER medal shows the intertwining, crowned ciphers of the Emperors Nicholas I and Alexander II topped by the all-seeing eye emanating flaming rays. The dates: "1853-1854-1855-1856" are placed under the ciphers. The reverse of the Medal is plain except for an inscription signifying: "We have Set Our Hopes in Thee O Lord, Let Us Never Be Ashamed".
DIAMETER: 28 mm
RIBBON: Modern suspension with the correct St.George ribbon