Georg Brandt was a Swedish

Sweden

Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....

 chemist and mineralogist who discovered cobalt

Cobalt

Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

 (c.1735). He was the first person to discover a metal unknown in ancient times.

Brandt was born in Riddarhyttan

Riddarhyttan

- External links :* *Images of , and by Jakob Ehrensvärd...

, Skinnskatteberg

Skinnskatteberg

Skinnskatteberg is a locality and the seat of Skinnskatteberg Municipality in Västmanland County, Sweden with 2,395 inhabitants in 2005.-External links:* - Official site...

 parish, Västmanland

Västmanland

' is a historical Swedish province, or landskap, in middle Sweden. It borders Södermanland, Närke, Värmland, Dalarna and Uppland.The name comes from "West men", referring to the people west of Uppland, the core province of early Sweden.- Administration :...

 to Jurgen Brandt, a mineowner and pharmacist, and Katarina Ysing. He was professor of chemistry at Uppsala

Uppsala

- Economy :Today Uppsala is well established in medical research and recognized for its leading position in biotechnology.*Abbott Medical Optics *GE Healthcare*Pfizer *Phadia, an offshoot of Pharmacia*Fresenius*Q-Med...

 University, and died in Stockholm

Stockholm

Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...

. He was able to show that cobalt was the source of the blue color in glass, which previously had been attributed to the bismuth

Bismuth

Bismuth is a chemical element with symbol Bi and atomic number 83. Bismuth, a trivalent poor metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally uncombined, although its sulfide and oxide form important commercial ores. The free element is 86% as dense as lead...

 found with cobalt. He died on April 29, 1768 of prostate cancer.

About 1741 he wrote: "As there are six kinds of metals, so I have also shown with reliable experiments... that there are also six kinds of half-metals: a new half-metal, namely Cobalt regulus in addition to Mercury

Mercury (element)

Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...

, Bismuth, Zinc

Zinc

Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

, and the reguluses of Antimony

Antimony

Antimony is a toxic chemical element with the symbol Sb and an atomic number of 51. A lustrous grey metalloid, it is found in nature mainly as the sulfide mineral stibnite...

 and Arsenic

Arsenic

Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

". He gave six ways to distinguish bismuth and cobalt which were typically found in the same ore

Ore

An ore is a type of rock that contains minerals with important elements including metals. The ores are extracted through mining; these are then refined to extract the valuable element....

s:

1. Bismuth fractures while Cobalt is more like a true metal.
2. In fusing, they do not mingle but attach about as an almond and its stone.
3. The regulus of Cobalt fuses with flint and fixed alkali giving a blue glass known as zaffera, sasre, or smalt
   Smalt
   Smalt is powdered glass, colored to a deep powder blue hue using cobalt ions derived from cobalt oxide . Smalt is used as a pigment in painting, and for surface decoration of other types of glass and ceramics, and other media...
   
   . Bismuth does not.
4. Bismuth melts easily and if kept melted, calcinates forming a yellow powder.
5. Bismuth amalgamates with Mercury; the regulus of Cobalt does not at all.
6. Bismuth dissolved in nitric acid and with aqua regia and gives a white precipitate when put in pure water. The regulus of Cobalt needs alkalies to precipitate, and then forms dark or black precipitates.

External links

• Georg Brandt
• "Brandt, Georg" by Uno Boklund in: Charles C. Gillispie, ed., Dictionary of Scientific Biography (New York, New York: Charles Scribner's Sons, 1970), vol. 2, pages 421-422.