43) Goddess of the Earth - Tellurium

Tellurium (Latin tellus meaning "goddess of the earth") was discovered in the 18th century in a gold ore from the mines in Zlatna, near today's city of Sibiu, Romania.
This ore was known as "Faczebajer weißes blättriges Golderz" (white leafy gold ore from Faczebaja, German name of Facebánya, now Faţa Băii in Alba County) or antimonalischer Goldkies (antimonic gold pyrite), and, according to Anton von Rupprecht, was Spießglaskönig (argent molybdique), containing native antimony. In 1782 Franz-Joseph Müller von Reichenstein, who was then serving as the Austrian chief inspector of mines in Transylvania, concluded that the ore did not contain antimony, but that it was bismuth sulfide. The following year, he reported that this was erroneous and that the ore contained mostly gold and an unknown metal very similar to antimony. After a thorough investigation which lasted for three years and consisted of more than fifty tests, Müller determined the specific gravity of the mineral and noted the radish-like odor of the white smoke which passed off when the new metal was heated, the red color which the metal imparts to sulfuric acid, and the black precipitate which this solution gives when diluted with water. Nevertheless, he was not able to identify this metal and gave it the names aurum paradoxium and metallum problematicum, as it did not show the properties predicted for the expected antimony.

Industrial and Commercial Uses
The first application of chemical bonding of tellurium was used in making the outer shell of the first atom bomb.
Tellurium has many unique industrial and commercial uses that improve product quality and quality-of-life. Many of these technologies that utilize tellurium have important uses for the energy industry, the military, and health industries. Tellurium is used to color glass and ceramics and can improve the machining quality of metal products. When added to copper alloys, tellurium makes the alloy more ductile, whereas it can prevent corrosion in lead products. Tellurium is an important component of infrared detectors used by the military as well as x-ray detectors used by a variety of fields including medicine, science, and security. In addition, tellurium-based catalysts are used to produce higher-quality rubber.
CdTe films are one of the highest efficiency photovoltaics, metals that convert sunlight directly into electrical power, at 11-13% efficiency and are, therefore, widely used in solar panels. CdTe is a thin-film semiconductor that absorbs sunlight.
Tellurium can be replaced by other elements in some of its uses. For many metallurgical uses, selenium, bismuth or lead are effective substitutes. Both selenium and sulfur can replace tellurium in rubber production.
Technologies based on tellurium have global impacts. As a photovoltaic, CdTe is the second most utilized solar cell in the world, soon said to surpass crystalline silicon and become the first. According to the US military, the tellurium-based infrared detectors are the reason that the military has such an advantage at night, an advantage which, in turn, has an effect on global and domestic politics.

Environmental Impacts
Tellurium extraction, as a byproduct of copper refinement, shares environmental impacts associated with copper mining and extraction. While a generally safe process, the removal of copper from other impurities in the ore is can lead to leaching of various hazardous sediments. In addition, the mining of copper tends to lead to reduced water flow and quality, disruption of soils and erosion of riverbanks, and reduction of air quality.

Resource Limitations vs. Demand
About 215-220 tons of Tellurium (Te) are mined across the globe every year. In 2006, the US produced 40% of production, Peru produced 30%, Japan produced 20%, and Canada produced 10% of the world's tellurium supply (since the chart can't be any bigger). The leading countries in production are the United States with 50 tons per year, Japan with 40 tons per year, Canada with 16 tons per year, and Peru with 7 tons per year (year 2009). When pure, Tellurium costs $24 per 100 grams. Because Tellurium is about as rare as platinum on earth, the United States Department of Energy expects a supply shortfall by the year 2025, despite the always improving extraction methods. As demand increases to provide the Tellurium needed for solar panels and other such things, supply will continue to decrease and thus the price will skyrocket. This will cause waves in the sustainable energy movement as well as military practices and modern medicine.

In Romanian Metaliferi Mountains, at Săcărâmb, where the average Au content over 200 years of mining is estimated at 10 g/tonne (Udubaşa & Udubaşa study, 2004), Ghiţulescu & Socolescu estimated a total mined quantity of Au and Ag of 85 tons untill 1941 (30 tons Au and 55 tons Ag). No data are available on the Tellurium content in the ore deposit or on the total Tellurium quantity mined. However, based on the Au:Te ratio of 1:2 in some of the most frequent Telluride occurring in the deposit (nagyágite and sylvanite), one can infer a Tellurium content 20 g/tonne and a total amount of 60 tons of Tellurium mined and unprocessed until 1941 (just dumped), from Săcărâmb ore deposit alone (as mentioned in the 2013 study: "Tellurium, Selenium and Cadmium resources in the waste dumps of Săcărâmb area: Apuseni Mountains, Romania. A preliminary estimation" – by Gheorghe C. Popescu, Antonela Neacşu, Mihaela Elena Cioacă & Grigore Buia).
According to another study: "Mineral assemblages at Săcărâmb", this mine has estimated reserves of around 10 million tons grading 1~2 g/tonne Gold in the salband ore (meaning a total amount of 20~40 tons of Tellurium; based on the Au:Te ratio of 1:2).

The Importance of Tellurium as a Health Hazard in Industry
Tellurium Resources
Mineralogy, Resources, Energetic implications
Delaware Mineralogical Society
Carpathian Journal of Earth and Environmental Sciences
Golden Quadrilateral, Romania
Gold Rush In Romania

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