Microscopic diatom shells are used to filter microbes and disease-causing viruses from public water systems. Diatomite is also used to filter sugar, oil, organic and inorganic chemicals, and various alcoholic beverages, including beer and wine.
Diatomite is a soft, friable and very fine-grained siliceous sedimentary rock composed of the remains of fossilized diatoms. Chalky to the touch and often light in color, diatomite can be white if pure, but more commonly it is buff to gray in situ, or sometimes black. Because of its low density and high porosity, it is extremely lightweight, and it is essentially chemically inert.
Its properties make diatomite very useful as a filtration medium as well as a component in cement. It is whitish, powdery, and very lightweight. It seems quite soft, but the individual particles making up the rock are siliceous opaline silica , having a hardness around 6 on the Mohs Scale.
This makes diatomaceous earth a wonderful mild abrasive. It is mined for use in a wide variety of products. Most people encounter diatomites everyday as one of the ingredients in toothpaste the opaline silica scrapes away foreign material from tooth surfaces.
Diatomites form by the accumulation of billions of diatom skeletons in lake or marine settings. It leaves hands dusty if touched and has a fragile feel as if it has a delicate and light-weight internal structure. This feeling is not misleading. Diatomite is composed of many unicellular algae with a hollow opaline test. Diatomite often floats in water just like pumice , at least initially before the pores are filled with water. The porous nature gives it many useful properties.
Diatomaceous earth is widely used in industry for many different applications. Pure diatomite is white as this sample from Armenia. Its width is 7 cm. Diatomite is friable and fragile very light-weight rock. Diatomaceous earth is usually known as diatomite to geologists but for the general public diatomaceous earth is much more frequently used term.
People who have experience with diatomaceous earth probably know it as a white powder, not as a rock type. However, this powder is directly manufactured from a naturally occurring rock.
There are more terms than diatomite and diatomaceous earth when referring to this material. German word kieselgur or kieselguhr has been used since the 19th century because first industrial scale mining of diatomaceous earth took place in Germany. This diatomite was used by Alfred Nobel as an absorbent and stabilizer for nitroglycerine. His invention which made the use of nitroglycerine much less hazardous is known as dynamite. It was the beginning of a large-scale diatomite use for industrial purposes although the material itself was known well before.
Diatomite was used in antiquity by the Greeks as an abrasive and in making lightweight building brick and blocks. Blocks of diatomite were used for the dome of the Hagia Sophia church in Constantinople now Istanbul in Turkey. This architectural wonder its diameter is 30 meters was much easier to construct with light-weight building blocks of diatomite 1.
Another term that may be encountered is tripolite. Originally it referred to diatomaceous earth deposits near Tripoli capital of Libya but in many cases the term has been applied to deposits far away from Libya. Hence, tripolite is just a synonym of diatomite. Diatomite deposits do exist in many places and are extensively mined nowadays because of its highly useful properties. The main producing countries are USA and China 1. Diatomaceous earth is composed of diatom frustules. Diatoms are a large group of mostly unicellular algae.
They live in both oceans and lakes and are one of the most common types of phytoplankton. Majority of diatoms use sunlight to photosynthesize, so they are producers in the food chain. They are not entirely symmetrical because one half of their frustule valves is slightly smaller than the other to fit inside the edge of it.
The majority of frustules are between 5 and micrometers in diameter 3. Dogs and cats can be treated with food-grade diatomaceous earth to control fleas and ticks. Before treating the pet, clean their bedding materials, and vacuum rugs where the pet is allowed to roam. Then lightly dust these areas with diatomaceous earth. Repeat every few days. To treat the pet, brush, comb, and inspect the animal to remove fleas and ticks. Then dust the pet lightly with diatomaceous earth. Bathe the pet after two or three days with a moisturizing shampoo.
After the bath, brush or comb the pet to remove any fleas or ticks that remain. Repeat dusting and combing every few days. Bathe the pet about once a month with moisturizing shampoo. Diatomite Producers: Twenty-nine countries produced commercial quantities of diatomite in Sixteen other countries produced less than 50, metric tons. In , a total of 29 countries produced commercial amounts of diatomite. The United States was the leader, producing an estimated , metric tons.
Czechia , Denmark and China each produced over , metric tons. Argentina , Peru and Japan produced , metric tons or more. Diatomite forms in marine water and freshwater environments. These origins are an important consideration when a diatomite source is being considered for use. Any use that will be associated with human, animal, or plant contact should come from freshwater deposits.
Diatomite from saltwater sources can contain salts that can produce objectionable or toxic effects. The cost of diatomite depends on its quality, how it will be used, and the preparation effort that has been invested by the supplier. Home » Rocks » Sedimentary Rocks » Diatomite Diatomite The sedimentary rock used as a filter, absorbent, filler, abrasive, and more. Article by: Hobart M.
Diatomite Information [1] Diatomite : Robert D. Crangle, Jr. Find Other Topics on Geology.
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