Sulfur from Bolivia (the world's most coveted and bright yellow colored sulfur in existence)

Sulfur is a chemical element with symbol S and atomic number 16. It is a yellow non-metal. Already in the 9th century BC. A mixture of sulfur, coal and tar was known to be extremely flammable and therefore it was regularly used in warfare. In the 12th century, gunpowder was invented in China, which was a mixture of potassium nitrate, charcoal and sulfur. In mythology, sulfur has often been associated with hell. Early alchemists used a symbol for sulfur consisting of a triangle with a cross on top. It had become known experimentally that sulfur reacts easily with mercury. Around 1774 it was the scientist Antoine Lavoisier who discovered that sulfur is a chemical element and not a compound. The name sulfur is believed to be derived from the Indo-European * suel- "to swell", "to boil". Sulfur is a non-metal with a bright yellow color. As an independent element, it is odorless. When burned, it emits a blue light, forming the stinging sulfur dioxide. It is insoluble in water, but dissolves well in carbon disulphide. Sulfur chemistry is an important branch of chemistry, mineralogy, environmental science and technology. The element itself forms a yellow crystalline solid with a rhombic crystal structure, which consists of an accumulation of ring-shaped S8 molecules. When powdered, the substance (except for the color) resembles wheat flour (also called sulfur flour). It's an insulator. At 112.8 ° C, sulfur changes into a monoclinic phase, which then melts at 119.0 ° C. The liquid first consists of S8 molecules and is then not very viscous. At higher temperatures, the viscosity increases enormously because ring opening and polymerization takes place. When the polymer melt is quenched in cold water, plastic sulfur is formed, an amorphous form which, however, gradually crystallizes. Sulfur boils at 444.674 ° C. On Earth sulfur is found in large quantities as a compound in minerals such as pyrite, galena, sphalerite, gypsum and barite. In volcanic regions it is found in its elemental form in small quantities, often in soles. Sulfur is frequently found on other planets with active volcanism. Jupiter's moon Io is a clear example. However, the main source of sulfur is the petrochemical industry, where sulfur-containing components are removed from gas and oil to obtain a cleaner fuel. For example, hydrogen sulphide is removed from gas by means of amine gas treatment and subsequently converted into elemental sulfur in the claus process. Sulfur occurs in all living things because the amino acids methionine and cysteine ​​contain sulfur compounds. This means that most proteins cannot exist without sulfur. Since petroleum is formed from organisms, the occurrence of non-elemental sulfur in it is not strange.