كليدواژه :
ايران , فلزگري كهن , مس آزاد , استحصال , مس ارسنيكي , برنز قلعي , برنج
چكيده فارسي :
فلزگري باستاني در ايران همواره فن و صنعتي در حال تحول بوده و ابداعات متنوعي در اين حوزه رخ داده كه از جنبه‌هاي فني و هنري و كاربردي منحصربه‌فرد و جالب‌توجه است. در اين مقاله تلاش شده تا شكل‌گيري و تحولات رخ داده در فلزگري آلياژهاي مس در دوران پيش از تاريخ ايران بر اساس يافته‌هاي باستان‌شناسي و مطالعات فلزگري كهن (آركئومتالورژي) مورد مطالعه و تحليل قرار گيرند. در اين مقاله ابداعات و تحولات رخ داده در حوزه فلزگري مس و آلياژهاي آن در حدود 6500 سال (بين حدود 7000 تا 500 ق.م) مورد معرفي فني و باستان‌شناسي قرار گرفته‌اند. نتايج مطالعات فلزگري در ايران نشان مي‌دهد كه اولين فلز مورد استفاده، مس بوده است. روند استفاده از اين فلز از دوره نوسنگي در فلات ايران آغاز شده و در طول چهار هزار سال از شكل‌دهي مس آزاد تا استحصال سنگ معدن‌هاي اكسيدي و سولفيدي در دوره مس‌سنگي ادامه يافته است. همچنين استفاده از آلياژهاي مس ارسنيكي، برنز و برنج از دوره مس‌سنگي تا عصر آهن از تحولات فلزگري مس در ايران بوده است. بر اساس نتايج ايران را مي‌توان يكي از نواحي پيشرو و مهم در شكل‌گيري و توسعه فلزگري آلياژهاي مس در دوران پيش از تاريخ دانست.
چكيده لاتين :
The Iranian Plateau and its residents can be enumerated as one of the pioneers in progress of
technology, science and knowledge in the ancient world. The development of metallurgy on the
Iranian Plateau has been a topic of interest to both archaeologists and scientists for many years
because of the remarkable history of the metallurgical activities in this region and concerned the
wide variety of the technologies, compositions, innovations, etc. (Figure 1). Results of many
investigations in metallurgy of ancient Iranian Plateau show usage of copper and its alloys in
different periods of Iran history from prehistoric to Islamic era. In this paper, formation,
evolutions and developments occurred in metallurgy of copper alloys have reviewed and in
prehistoric period of Iran (7000-500 BC) based on archaeological and archaeometallurgical
investigations. The results of analytical and archaeological studies state the first metal used in
prehistory of Iranian Plateau has been copper. It is apparent that the Iranian Plateau has a
significant history in the metallurgy of copper and its alloys in the prehistoric period. It has
begun in the Neolithic period and during 4000 years has transformed from forming objects by
hammering native copper to extensive smelting of oxidic and sulphidic ores in Chalcolithic era.
The ancient metalworkers used native copper to manufacture small decorative objects, as it was
observed in Ali Kosh Neolithic site (Figure 2). It was developed by shaping native copper to
produce small functional objects such as objects discovered from late Neolithic sites (Figure 2).
It was continued by melting native copper to cast objects. Furthermore, metallurgical processes
were extended by smelting copper oxidic ores in crucibles during 5th and 4th millennium BC. In
fact, the chalcolithic period (ca. 4500-3000 BC) is the period of emergence and development of
smelting of oxidic and then sulphidic copper ores in small scale. There are numerous evidences
of copper smelting in the chalcolithic archaeological sites such as Qabristan, Tal-i Iblis, etc.
showing the crucible smelting technology in different regions of the Iranian Plateau (Figure 3).
This technology was developed by large-scale smelting of copper ores, as it was discovered in
Arisman, near Kashan. Of course, the metallurgical technologies during the late chalcolithic
period (ca. 3500-3000 BC), is a mixture of crucible smelting and furnace smelting (Figure 4). It
is worth noting that the main metallic composition in the Chalcolithic period is arsenical copper
that may has been produced accidentally by smelting As-bearing copper ores leading to obtain
metallic copper with significant amounts of arsenic (Figure 5). Nevertheless, some evidences of
intentional arsenical copper production have been found during late Chalcolithic and early
Bronze Age archaeological sites, such as Arisman.
The third millennium BC was occurred with occurrence of a new alloy, tin bronze. Early
evidences of this technology was observed in western Iran, Luristan at the beginning of the third
millennium BC. Some tin bronze objects with significant amounts of tin were detected among copper and arsenical copper objects discovered from Early Bronze Age graveyards such as
Kalleh Nisar and Bani Surmeh (Figure 6). Although, early evidences of tin bronze metallurgy
have been occurred in the third millennium BC but this technology was limited for about 1000
years in western and south-western Iran. Results of analytical studies revealed that the main
copper base metallurgy has been copper and arsenical copper in other regions of the Iranian
Plateau during the third millennium BC. Tin bronze was emerged in central Iran during the
middle and late Bronze Age (ca. 2500-1500 BC) such as evidences from Malyan (Fars).
Therefore, no evidence of tin bronze has been observed in eastern Iran, even at the mid of the
second millennium BC. Although tin bronze was occurred during the early Bronze Age and was
spread during middle and late Bronze Age in western and central Iran, but it was the main
copper-based alloy during the Iron Age of the Iranian Plateau (ca. 1500-550 BC). Results of
analytical investigations states that tin bronze has been the main material in production of
metallic objects at the whole of the Iranian Plateau. The ritual objects from Iron Age graveyards
of western, northern and central Iran show application of tin bronze to produce these objects.
The large scale tin bronze production is the Iron Age of Iran is an interesting aspect, as this
alloy has been observed in different archaeological sites such as Hasanlu and Marlik (Figure 7).
One of the important collections form this category are the Luristan Bronzes, the enigmatic and
extraordinary metallic objects that were produced in high-quality craftsmanship and were placed
in graves and sanctuaries as ritual objects (Figure 8). The results of chemical analysis on the
Luristan Bronzes, as well as other tin bronze objects from Iran, shows that thy may have been
produced by uncontrolled alloying methods. In fact, controlling tin content has not been an
important case for ancient metalworkers during the Iron Age (and also the Bronze Age). Also,
no correlation between tin content and object’s typology is visible in the tin bronze objects from
prehistoric Iran, that is in contrast with accent cuneiform texts from Mesopotamia. It may show
that tin bronze metallurgy in the Iranian Plateau may has not been in connection with the
Mesopotamian technology. Although, evidences of copper-zinc objects have been observed
among the other copper based artefacts from second and first millennium BC, but it can’t be
stated that this material has been used as a deliberately produced metallurgical product. It is
more probable that these limited examples of copper-zinc objects (probably brass) were
produced by smelting Zn-bearing copper ores. Nevertheless, evidences of low-zinc objects from
Tappeh Yahya (southern Iran) and Luristan shows occurrence of early brasses (probable
accidentally) during the prehistoric Iran.
Results of numerous analytical studies on the prehistoric copper base metallurgy during the last
decades revealed interesting aspects of this technology from about 8000 BC. It has been started
by using native copper and then developed by smelting oxidic and sulphidic copper in crucibles
during the Neolithic and Chalcolithic periods. Large scale smelting sites also were occurred
during the late chalcolithic and early Bronze Age. Furthermore, application of different copper
alloys such as arsenical copper, tin bronze and brass from Chalcolithic to Iron Age are important
developments in archaeometallurgy in Iran. Totally, process of formation and development of
copper metallurgy in prehistoric Iran has been introduced and revised based on technical and
archaeological finds belonging a period about 6500 years (Figure 9).
