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 opper, which has been in use for about 7,000 years, was the first metal to be manipulated by humans. The word "copper" is from the Latin cuprum for "cyprian metal" referring to the major source of copper in the Mediterranean, the island of Cyprus. The Gaelic word for copper is umha, a term that is also applied to bronze and sometimes brass, all of which contain copper. Another term for copper is créad-umha, a word that may have more to do with a finished piece of copper work because of compounding umha with the term créad referring to craft.
Much like gold, copper is soft enough to be shaped by pressure without needing to be heated. Because of this it's quite possible that the first copper tools were shaped by pounding the raw ore with a stone hammer. However it is easier to work with, and less brittle, when heated. In Ireland, the early agriculturists began working with copper sometime near 4000 bce. In these earliest times, the people may have relied on ground level deposits though mining quickly became an important industry. How do you find copper? Telltale signs of its presence are traces of green malachite and blue azurite the blues and greens of oxidized copper. By about 2900 bce dozens, if not hundreds of mines dotted the landscape. Geologist John Jackson estimates that the pre-historic copper mines of counties Cork and Kerry produced some 370 tones of finished copper. So far only about 800 kilograms or 365 pounds of copper and bronze artifacts from the early Bronze Age have been recovered. Even with the possibility of more finds in the future the sheer volume of mined ore points to a thriving, well organized metal industry and export trade. What would those early mines have looked like? While most are now beneath water level or submerged in bogs, one dating to c. 1500 bce has been excavated. The entrance is less than 3.5 feet high, angling down about 25 feet to a cut rock room no more than about 5 feet high and about 16 feet wide. Cramped, dark and damp. The words for miner, mine, mineral, ore have interesting clues about social development. All of these terms come from the common root word mian, a root term also used to define humanities less than graceful qualities such as greed, covetousness, lust, longing as well as desire, pleasure and luxury. Very interesting! Now that we've got our ore out of the ground how do we refine it? We build a furnace!! Archeological evidence indicates that an open-air bowl furnace was in use in relatively unchanged form from the early Bronze well into the Common Era. Initially this furnace would have consisted of a fairly shallow hole dug into the ground. The hole was lined with clay, charcoal (fioghual) made of birch or oak wood was placed in a layer on top of the clay, this was then covered by ore. If we were smelting copper the heat of the charcoal, which is higher than that of wood, would melt the ore. The charcoal also releases gazes that react with the copper minerals to reduce them to copper metal. As the copper melts, a molten mass is formed covered by lighter waste material called slag, which, once the metal has cooled, can be broken off leaving a cake of pure refined copper. Copper casting was accomplished by using a one piece carved stone mold (múnla). Though most molds held only one template some have been found with two. One unique mold found in Co Carlow held templates for eight axes. When a single mold had multiple templates this was often of the same type of object with a variation in design or more rarely of two different types of object such as an axe and a dagger. The most commonly found cooper artifacts are axes along with awls and tanged daggers. Soon after cast copper came into use, bronze was developed. Bronze is made by adding 10% tin (stán) to copper. Bronze is a harder metal that can better withstand hammering while still hot. This technological innovation led to the development of greater range of products. While stone mold technique was applied to smaller cast bronze objects, clay molds came into use with the advent larger cast pieces such as swords. When iron came into use, the basic furnace had to be modified on account of the higher temperature needed to refine the ore. This modification involved adding a domed cover to the forge. This cover was made of clay or sod and soil. Bellows were also developed to keep the fire red-hot, raising the temperature within the furnace to the 1100 to 1200°C needed to refine iron ore. To produce a given amount of refined iron, a large amount of raw ore is required, only 20% of the total bulk of the ore produces usable iron. As with copper, the ore was placed in the furnace on a bed of charcoal and heated. The high temperature caused the slag or waste to sink to the bottom leaving the "bloom" a spongy mass of iron particles and impurities, on top. Once separated from the slag the bloom was reheated to a higher temperature and beaten on an anvil to cause the iron particles to bind together and to remove the remaining impurities. From then on it could be forged or cast at will. It is during the early to mid Bronze Age that ornamental work of beaten gold began to appear. By the Late Bronze Age objects formed of solid gold bars or heavy wire such as massive torcs and pins became the fashion among those who could afford them. This gold industry reached its height from 800-700 bce. In conjunction with a developing technology and trade in bronze and the use of gold in personal ornamentation, we see a rapid increase in the manufacture of swords, shields and halberds. This phenomenon indicates that from this point on the social structure which had remain relatively unchanged for hundreds of years was about to undergo a rapid and complete transformation. What was society like during this period? From recovered artifacts we can see that weapons manufacture was on the increase. During the early Bronze Age most metal objects were utilitarian, axes to fell trees for pastures and crop-land, as well as farm and household equipment. From the mid to late Bronze Age we see a rise in weapons production. From the estimated number of mines and the volume of ore they would have produced, as well as the size and quantity of gold jewelry recovered, we can deduce that metal work was creating a great deal of prosperity. With prosperity came tribal and clan rivalries and increased violence. Metal work became to a large extent responsible for the well-being and prosperity of the tribe. Tribal chieftains were quick to want to protect and control this source of wealth. It is now that we begin to see increased specialization in occupation. The degree of skill and sophistication in some of the objects points to established workshops where skills and techniques could be developed, workshops under the patronage of increasing powerful ruling families. Competition for control and status fostered inter-tribal tensions leading to increased development and manufacture of weaponry, a shift towards fortified settlements, an increasingly structure and stratified society and the development of a patriarchal aristocratic warrior class. It was during this time that iron (irann) emerged. Some of the earliest signs of iron-work, dating to about 700 bce, are found at Fort Navan (Emain Macha). The early objects show a quick adaptation of bronze work techniques though the metal still contained a large amount of impurities. Copper refining had to be modified to adjust to the differences of iron. It wasn't until 300 bce that iron became predominant in the manufacture of weapons. Weapons, namely swords and spearheads in this form the bulk of surviving iron artifacts from the Irish Iron Age and show the characteristic La Tène style predominant in that era. Even with the development of iron-work, bronze continued to be used for household, farm and personal items. |
