#pure element

[mineralsandsomerocks]

Silicon

Locality: Freiberg, Mittelsachsen, Saxony, Germany

99.9999% Purity, manufactured by Wacker AG

[housecatchem]

Manganese

The collection of elements: High purity (99,9%) manganese metal flakes obtained by electrolysis.

A silvery grey, hard and very brittle metal that looks like iron. 

[subsolidus-blog]

The Purity of Brimstone

                            subsolidus Creative Commons BY-NC-SA

What is a mineral? The question seems simple. It is a pure inorganic compound that is naturally occurring and can be found in the Earth. But what about substances that only partially fit this definition? Anthracite is a naturally occurring pure compound that can be found in the Earth, but it is biogenic in origin, all of the carbon contain in a piece of anthracite is derived from living organism. Is anthracite a mineral? What about crude petroleum? Or what about mercury? Mercury is a naturally occurring pure substance d that is found in the Earth. But it is a liquid with no crystalline structure, and it is a pure element not a compound. Are any of these materials minerals? Clearly our definition of what is a mineral is far from perfect. The natural world has an incredible diversity that so often defies categorization.

 So far all of the minerals we have examined have been “minerals proper.” They fit the textbook definition perfectly. They have a determinate chemical composition, are naturally occurring, are found in the Earth, and are inorganic. Naturally, today we will be looking a substance that doesn’t quite fit that mold. The substance we are looking at today is Sulfur.

 Sulfur is a substance that humans are almost universally familiar with. The word “sulfur” brings to mind thoughts of pungent odors, gunpowder, and the color yellow. Indeed, sulfur has all of these attributes. But why are we discussing it in a mineral blog? It is because sulfur, despite not being a chemical compound, is actually classified as a mineral.

 Despite minerals commonly being thought of as chemical compounds there are a number of minerals that are not at all compounds, but are in fact pure elements. This means that they are comprised of a pure single element without anything else in them. Copper, Silver, Gold, Mercury, Tin, and, of course, Sulfur, can all be found in a more or less naturally pure state in the Earth. In these instances they are considered to be minerals. However, in the case of the metals the term “native metal” is more commonly used, and is generally preferred.

 Sulfur is an enormously useful material. In addition to being an essential nutrient for all metazoans including humans it is one of the most significant industrial materials in the world. Every year thousands of metric tons of sulfur are consumed by the chemical, fertilizer, and pharmaceutical industries. Without cheap and highly pure sulfur the modern world would grind to a halt.

 From a collector’s standpoint, native metals and elemental minerals provide many unique and beautiful possibilities. Even sulfur, a proletariat material if there ever was, can be a beautiful and unique sample. Big samples can have large crystalline faces that reflect light with a characteristic waxy luster. Sulfur has a certain translucency to it that is unlike most other materials; it seems to reflect light internally as well as externally. A good piece of sulfur is practically a necessity in any mineral collection. Just don’t mind the smell.