Archaeologia Islandica - 01.01.2007, Blaðsíða 71

Ancient ironmaking in Iceland, Greenland and Newfoundland
Figure 11. Þjórsárdalur. The magnet indicates an entrapped fragment of iron. Photo Jón by
Halfdanarson.
sponding consumption of ore and produc-
tion of metallic iron, denoted by Y and
X. Only two equations are needed. Let us
choose mass balances for iron and silica
with values from the slag heap at Belgsá,
Bl-OreB:
Iron: Y x 0.594 = X + 10 x 0.488
Silica: Y x 0.0989 = 10x0.249
giving Y = 25.2 kg and X = 10.08 kg.
An identical calculation for Slag B2-Ore
B gives Y = 22.5 kg and X = 8.5 kg.
In principle mass balances might have
been applied for Fe + Al, in the present
case not leading to any great change. Fe
+ Mn seem to be less reliable due to small
percentages. This leads to a ratio of iron
to slag close to 1 : 1 and a total production
of at least 500 tons at the sites Vidivellir
and Belgsá. If distributed over a period
of say 250 years, this corresponds to an
annual production of 2 tons.
Organization and trade
Two of the three sites studied lie in or near
farmyards. The smelting itself must have
been integrated into everyday farm life,
to an extent hardly known in Norway. As
there is little or no debris from furnaces,
one would also assume that they had a
relatively permanent character and/or the
stones were removed to be used for other
purposes. However, we do not know the
details of construction. One should take
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