Horseman advancing right, holding a spear, letters "FC" below / Inscription in five lines "KNZ / bVELIKIY / IBAN / VSEYA R / USY" ("Grand Duke Ivan of all Russia"). 14mmx11mm, 0.65 grams. Novgorod mint. Griszin #76; Russian Wire Coins #76.
This is a full kopeck (not a denga), weighing 0.65 grams. The coin was minted in Novgorod around 1540 when Ivan was still just a Grand Duke and not a Tsar.