New Mexico Mineral Symposium — Abstracts

Traditionally, the ages of ancient history are divided based upon the material used for tools and weapons resulting in the Stone Ages (Palaeolithic, Mesolithic, and Neolithic), Chalcolithic (Copper Age), Bronze Age, and Iron Age.

Even in the earliest of these time periods, the Palaeolithic, mining was actively undertaken. These early mines were often surface trenches or shallow bell pits used to extract chert for tools or minerals for making pigments. Mining tools used during this time were mostly hammerstones and horn picks, which were only effective in working softer sedimentary rocks. By the Neolithic, underground mines had grown in size, but were still shallow. Stone, bone, and antler tools were also still used. The Chalcolithic marks a major advancement in mining technology. Metals, especially copper, were extracted using firesetting to soften hard rocks. In addition, the development of smelting allowed people to separate metal from ore minerals such as copper carbonates and copper sulphides. Casting methods, including lost wax casting, were also developed at this time. Advances continued into the Bronze Age when in addition to firesetting, bronze tools were used, which allowed underground mines to become deeper and more expansive. The first documented use of iron and thus the beginning of the Iron Age was by the Hittites in present-day Turkey. Although iron is more difficult to smelt that other metals, this new technology spread across Europe.

The high point of the mining industry in the ancient world was with the Romans, who operated both open-cast and underground mines throughout the empire. Romans still used firesetting to weaken rock, but also used iron tools such as picks, gad bars, and battering rams. When geologic conditions were favorable for it, they employed a form of hydraulic mining. Roman mining resembled modern mining in several ways. The Romans began timbering their underground mines as well as using room and pillar methods. Ore was extracted from shafts using a windlass and basket or bucket. Illumination of underground mines was accomplished with oil lamps. These lamps were also used to test air quality and determine where dedicated ventilation shafts were needed. The Romans used several methods for dewatering deep mines, including French drains, bailing buckets, screw pumps, and waterwheels.