In 1782, Franz Joseph Müller von Reichenstein, a Romanian mining official and amateur chemist, discovered the element tellurium. Reichenstein extracted the element from a sample of gold ore and originally thought it to be the element antinomy, which is very similar in appearance. It did not take him long to realize that it was a wholly new element. It was not until 1798, however, that the element was recognized after being mentioned in a paper by German chemist Martin Heinrich Klaproth. Klaproth gave Reichenstein the credit for the discovery. The element's name comes from the word tellus, which is Latin for earth.
Tellurium is a silvery-white, metallic looking, semi-metal element. As a semi-metal, it possesses attributes of both metallic and non-metallic elements. The crystalline structure is hexagonal in shape. The nucleus of a tellurium atom consists of 52 protons and 76 neutrons. Around the nucleus are five energy levels, which hold 52 electrons at varying distances from the nucleus.
At room temperature, tellurium is a solid that falls between gypsum and calcite in level of hardness with a score of 2.3 mohs. This means it is fairly easy to break apart. It has a relatively high melting point of about 841 degrees Fahrenheit and boils at around 1,814 degrees. It is a poisonous substance that can be hazardous if inhaled and causes a garlic smell on the breath.
The element has a number of uses such as being added to copper and stainless steel to make them easier to work with. It is sometimes used to add color to glass and ceramics for decorative work. Tellurium is one of the main ingredients in the manufacture of blasting caps for explosives. It is also mixed with lead to increase resistance to sulfuric acid. In electronics, it is used in conjunction with cadmium and mercury to make photosensitive semi-conductors.