OJAMO IRON MINE

Production of iron wasn’t unknown in Finland in the 16th century. Peasants had produced iron for their own needs from the minerals taken from the lake and swamp bottoms for centuries. When the Middle Ages ended there was more demand for iron because iron articles were used more and more as tools and weapons especially in manor houses. An old document proves that King Gustav Wasa gave his gracious approval for the utilisation of the iron ore to Erik Fleming, the lagman ("sheriff") of Southern Finland. The iron ore was found in the village of Ojamo in Lohja. This happened September 15th , 1542. The first industrial-like enterprise in Finland was born.

Photograph © Lohjan museo
The Ojamo iron mine in the 19th century, some decades after the work in the mine was stopped finally. Ojamo manor house which was built in the beginning of 19th century is behind.

Fleming got workers from Germany for his newly formed mine because in Germany mining was more advanced than in Sweden. Those days minerals were mined so that the hill was heated up by burning the trees which were next to it for 24 hours. After that the men went down to the smoky mine to stop the fire. The coal was cleaned from the top of the hill after which it was soaked with cold water. The sudden cooling down of the rock made it crock and crumble. After this the chunks were taken off with a crow bar and pick axes. The forests of the nearby areas were cut down almost completely because the burning of the trees next to the hill took up so many trees. Powder was used from the end of 16th century.

Photograph © Lohjan museo
Lifting of stones and pumping of water from the mine.

After that the minerals were moved by carrying or pushing a cart which would lift them up. The water pumps usually worked by animal power. The minerals mined were taken to Mustio which is situated in the estuary of the river Mustio which runs from Lake Lohja to the sea. The place was ideal because of its good transportation connections and because there was a source of waterpower. The first ironworks ("Ruukki") in Finland was founded in Mustio. The ore was taken by barge from Ojamo to Mustio to be melted and forged there.

Two schemes of the mine from 18th century

Erik Fleming´s death stopped almost totally the large scale mining in the year 1548. King Gustav II Adolph visited Ojamo 1615 and demanded that the mine should be opened again. He needed iron for the funding of the widening wars in Central Europe.

The mine which had been abandoned for decades was full of water and trash. The water was pumped away. The mine was used until the 18th century, but the work was stopped and the mine abandoned because of the poor quality of the ore. The mine was optimistically opened for the third and the last time in 1824 and the work continued until the year 1850. Then the mine was permanently abandoned. It was finally proved that there was no more good minerals left.

The remnants of the iron mine are located today on the shore of lake Lohja in the garden of Ojamo manor house about 2 kilometres from the centre of Lohja. The manor house and the mine area have been privately owned and therefore closed for public eyes until recently. The last owner died in 1997. In his will he surprisingly gave the manor house and the other properties to the Historical Society of Lohja. Maybe in the near future the mine area will be opened as a museum.