The cache was found in a basement in the former Senate building of Moscow's ancient fortress, home of tsars and pretenders throughout centuries of turbulent history. Restoration began on the 18th-century building in April.
'Earth was being cleared out so pipes could be laid and, since there were cultural artefacts dating from the Middle Ages, we were able to find the cache there too,' she said. 'It was buried 5m (16ft) under a basement floor. Unfortunately, at the moment of the find, there was a spade blow so the jug which contained the coins - a little clay jar with a handle - was broken.'
The 3,426 silver Russian kopecks and one Polish coin were minted all through the 16th century - the period of Ivan the Terrible and Boris Godunov's reigns, and an age of siege, armed upheavals and betrayal remembered as 'the time of troubles'.
At the time of their burial the coins were worth about 35 roubles - a considerable fortune. A horse or cow cost about one rouble.