With the end of the XIII century, the Northern ("Novgorod"), the hryvnia was little changed - reduced the fineness of silver, there was a thickening in the Central part. At about this time, the ingots of steel to cut into pieces for smaller calculations (pressure from the Golden Horde waned and the trade in Russia is growing again). In the Baltic chronicle 1399 first mentioned the word "ruble", but it appeared earlier, probably just from the word "hack".
The photo shows poltinas of the State historical Museum. The weight of each is approximately 100 grams (ie half the hryvnia-bullion).