This is the chalice which I was given to use for Mass a week ago in Helsinki. I emailed Marko Tervaportti for some further information about it and he has kindly replied with the information that it was made in Paris, probably around 1870 and is thought to be a gift from the Countess Leopoldina Cicogna (from Milan) who brought it from France together with many other objects, including another precious chalice with standing figures of the four Apostles, and the Way of the Cross which still hangs from the walls of the Cathedral.
The Emperor, Czar Alexander II, gave permission for the building of St Henry's Cathedral at the request of Leopoldina's husband, Count Berg.
Here is a close-up of the base of the chalice in which you can see the painted glass medallion of Saint Joseph and Our Blessed Lady. The third, hidden from view, is a medallion of the crucifixion. Following the advice of J B O'Connell, I used this to orient the chalice whilst saying Mass so that I knew to drink the ablution from the same side of the chalice as that from which I had received Holy Communion. Just another of those little details that one can also observe when celebrating the Novus Ordo.