Timna ValleyThe Timna Valley (תִּמְנָע, timˈna(ʕ)) is located in southern Israel in the southwestern Arava/Arabah, approximately north of the Gulf of Aqaba and the city of Eilat. The area is rich in copper ore and has been mined since the 5th millennium BCE. During early antiquity, the area would have been part of the Kingdom of Edom. A large section of the valley, containing ancient remnants of copper mining and ancient worship, is encompassed in a recreation park. Ramon Airport is located near the entrance to the Timna Valley.
Leaching (chemistry)Leaching is the process of a solute becoming detached or extracted from its carrier substance by way of a solvent. Leaching is a naturally occurring process which scientists have adapted for a variety of applications with a variety of methods. Specific extraction methods depend on the soluble characteristics relative to the sorbent material such as concentration, distribution, nature, and size. Leaching can occur naturally seen from plant substances (inorganic and organic), solute leaching in soil, and in the decomposition of organic materials.
AdzeAn adze (ædz) or adz is an ancient and versatile cutting tool similar to an axe but with the cutting edge perpendicular to the handle rather than parallel. Adzes have been used since the Stone Age. They are used for smoothing or carving wood in hand woodworking, and as a hoe for agriculture and horticulture. Two basic forms of an adze are the hand adze (short hoe)—a short-handled tool swung with one hand—and the foot adze (hoe)—a long-handled tool capable of powerful swings using both hands, the cutting edge usually striking at foot or shin level.
CupellationCupellation is a refining process in metallurgy in which ores or alloyed metals are treated under very high temperatures and subjected to controlled operations to separate noble metals, like gold and silver, from base metals, like lead, copper, zinc, arsenic, antimony, or bismuth, present in the ore. The process is based on the principle that precious metals do not oxidise or react chemically, unlike base metals. When they are heated at high temperatures, the precious metals remain apart, and the others react, forming slags or other compounds.
AlcoaAlcoa Corporation (an acronym for "Aluminum Company of America") is a Pittsburgh-based industrial corporation. It is the world's eighth-largest producer of aluminum. Alcoa conducts operations in 10 countries. Alcoa is a major producer of primary aluminum, fabricated aluminum, and alumina combined, through its active and growing participation in all major aspects of the industry: technology, mining, refining, smelting, fabricating, and recycling. On November 1, 2016, Alcoa Inc.
Haya peopleThe Haya (or Bahaya) are a Bantu ethnic group based in Kagera Region, northwestern Tanzania, on the western side of Lake Victoria. With over one million people, it is estimated the Haya make up approximately 4% of the population of Tanzania. Historically, the Haya have had a complex kingship-based political system. Agriculture, particularly banana farming, is central to Haya economic life. They are credited with the independent development of carbon steel dating to 2000 years ago using pre-heating techniques.
Arsenic poisoningArsenic poisoning is a medical condition that occurs due to elevated levels of arsenic in the body. If arsenic poisoning occurs over a brief period of time, symptoms may include vomiting, abdominal pain, encephalopathy, and watery diarrhea that contains blood. Long-term exposure can result in thickening of the skin, darker skin, abdominal pain, diarrhea, heart disease, numbness, and cancer. The most common reason for long-term exposure is contaminated drinking water.
Roasting (metallurgy)Roasting is a process of heating a sulfide ore to a high temperature in the presence of air. It is a step in the processing of certain ores. More specifically, roasting is often a metallurgical process involving gas–solid reactions at elevated temperatures with the goal of purifying the metal component(s). Often before roasting, the ore has already been partially purified, e.g. by froth flotation. The concentrate is mixed with other materials to facilitate the process.