The Archaeology of Britain: An introduction from ... - waughfamily.ca

The Iron Age
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PRODUCTION AND EXCHANGE
The manufacture and exchange of finished goods became increasingly complex during the Iron
Age (Morris 1994). Three levels of craft activity are identifiable: output to meet individual
household or community needs; more specialized products for wider distribution; and luxury
goods for the wealthiest sections of society. For most commodities, little or no evidence of
production sites has survived, and the finished goods provide our main guide to the organization
and scale of activity. Only a minority of craft workers are likely to have been full-time specialists;
many activities, such as coastal salt production, metal ore extraction and pottery manufacture,
could have been carried out by ordinary agricultural communities at slack times.
Significant technological advances during the Iron Age included the introduction of lathes for
turning wooden and shale objects; the potter’s wheel; and the ability to make glass beads and
bracelets. In bronze-working, the use of lost-wax casting became widespread, and both gilding
and tin-plating were introduced late in the period. Other important innovations included the
development of the rotary quern for grinding grain and the introduction of iron-tipped plough
shares, which greatly facilitated the cultivation of heavier soils.
Successfully forging iron into durable artefacts required new skills and techniques, and was
extremely time-consuming, helping to explain why iron objects were relatively scarce until after
the mid-first millennium BC. Unlike bronze, iron could not be cast because the available bowl
furnaces were unable to achieve sufficiently high temperatures. On smelting, a spongy mass
(‘bloom’) collected in the furnace base, and had to be repeatedly heated and hammered to remove
slag and impurities. Since artefacts produced in this way were not inherently superior to bronze,
the principal reasons why iron was adopted were presumably that most parts of Britain have
access to iron ore and that wrought iron could be forged into shapes that bronze could not. While
the earliest iron artefacts—like the sword and sickle from the Llyn Fawr hoard (Glamorgan)—
are simply bigger versions of existing bronze types, new tool types, better suited to the tensile
properties of wrought iron, were gradually developed, including cutting discs, shaft hole axes,
shears, and tongs. Many types of edge tools in use by the Later Iron Age remained essentially
unchanged until the Industrial Revolution (Figure 7.9).
Most Iron Age settlements yield evidence of iron smithing, although this may simply indicate
that metalworkers visited periodically to make and repair implements. Smelting was generally
carried out away from the homestead. Two exceptions are the early Iron Age settlement at
Brooklands (Surrey), where areas were set aside for smelting and for forging, and the Later Iron
Age defended site at Bryn y Castell (Gwynedd), where furnaces inside the enclosure were used
for refining raw blooms; a more extensive iron-working area was located outside. At both sites,
the output was probably sufficient only for local needs.
Comparatively few artefacts show evidence for advanced techniques like the deliberate use of
steel, or even quenching and tempering, but smiths gradually learned enough about the properties
of different ores to choose those best suited for particular tasks; thus implements like adzes and
large sickles were generally manufactured from high-phosphorous ores, while high-carbon ores
were used for chisels (Ehrenreich 1985). As the period progressed, the best ores—from areas like
Northamptonshire and the Forest of Dean—were increasingly exploited. By the third century
BC at latest, good quality iron was exchanged over considerable distances as standardized ingots.
These were clearly of considerable value, frequently being hoarded or used as offerings. Three
main forms are known: sword-shaped bars, spit-shaped bars and ploughshare bars; but detailed
examination reveals over 20 types, each potentially indicating a different source. Stone weights
found at many Iron Age settlements similarly imply an interest in standardization and equivalence
in other spheres of exchange.