As used in water chemistry, a collective term encompassing dissolved, undissolved, and colloidal silica. In undissolved form, it exists as minute particulate and as encapsulated silica. In dissolved form, it can appear as a silicate, silicon dioxide and as silicic acid
a mineral compound composed primarily of silicon as silicon dioxide and is the major component of sand and glass. It is an excellent absorbent for many organic compounds. Nutritionally consumed through supplements such as diatomaceous earth, kieselguhr, and in the herb horsetail. Horsetail is the preferred method of consumption since it contains organic forms of silicon that are better assimilated and absorbed by the body than are inorganic forms of silicon. Silicon is a good elemental mineral nutrient for strengthening hair, bones and nails.
The primary glass forming oxide used in pottery. Boron is the other glass forming oxide used although more commonly as a flux than as a glass former due to its low melting point (577 C, 1063 oF). A glass forming oxide must be present in any glaze and as silica's melting point is 1800 C, 3272 oF, a flux is always present to reduce the melting point to a workable range. Pure boron glasses are water-soluble so of little use but Boro-sillicate glasses have a very low thermal expansion and are the main constituent of 'Pyrex' etc. Also see Dunting.
The molecule formed of silicon and oxygen (SiO2) that is the basic building block of volcanic rocks and the most important factor controlling the fluidity of magma. The higher a magma's silica content, the greater its viscosity or "stickiness."
Crystalline silica is the scientific name for a group of minerals composed of silicon and oxygen. The term crystalline refers to the fact that the oxygen and silicon atoms are arranged in a three-dimensional repeating pattern.
Abscesses, wounds that are slow to heal, toothache and earache, and similar localized infections. Silica is a mineral prepared from sand or flint rock. Homepaths tend to use it more for long-term prescriptions than for everyday ailments. However its can be very useful for treating pus-filled or suppurating wounds, since it encourages the body to expel diseased tissues, or to break down and reabsorb them.
The most common substance on the surface of the earth and a common component of rocks and soils. Pure silica is the mineral known as quartz and is composed of two atoms of the element oxygen (the most abundant element in the earth's crust) and one atom of the element silicon (the second most abundant element). Various forms of silica combine with other elements (aluminum, sodium, iron, etc) to create silicic minerals which are constituents of most rocks of the earth's crust. Common rocks contain from about 45% to over 75% silica in one form or another. Back
A mineral commonly found everywhere, and used by plants and animals in many ways. The beach is made of fine grains of silicates (silicon and oxygen) called sand, in which many animals and plants live. Some plants take in silica and use it as a defence - such as the horsetails that edge the grooves in their stems with silica to make them sharp and deter grazers.
Naturally occurring crystals of silicon compounds. Toxicology inert except when inhaled. Some types of silica produce silicosis, a scarring of the lungs similar to that produced by asbestos. Crystalline silica can also cause lung cancer (NTP,1991). Many forms of silica are used in consumer products, not all of which are equally dangerous. Often used as abrasives in scouring powders, polishes, etc.
SiO2; ocurring in crystalline (quartz), cryptocrystalline (very finely crystalline; crystals are very, very small) (opal) and non-crystalline (chert) forms; one of the most common minerals in the crust of the earth; an important mineral in the process of silification; also see permineralization
SiO2; Silicon dioxide; hard mineral; major inorganic component in plants; content in plants up to 15% of dry weight; dissolves in alkaline solutions such as alkaline pulping liquor; does not dissolve into acids, such as formic acid in the Chempolis process. See also: silica problem
Silicon dioxide. This is a very common material, often forming the mineral quartz, but also forming flint, agate and much of the sand found on beaches and in sandstones. Silicon and oxygen are both very common elements in the crust of the Earth, and therefore the proportion of silica present is used as a means of classifying igneous rocks into acid, intermediate and basic, the first being the richest in silica.
(Silicon Dioxide) A hard, white or colourless substance, that in the form of quartz, enters into the composition of many rocks and is contained in sponges and certain plants. The needle in the mouth of a female mosquito is made of silica. Flint, sand, chalcedony, and opal are examples of silica in different forms.
Naturally occurring silica occurs in deposits which are 99 percent silicon dioxide. The hardness provides both mechanical strength and abrasion resistance. Silica's are an economical extender-filler which is thermally stable, pure, low in ionic impurities, and hard. They are often used as antiblocking agents in polyolefin's.
In addition to the well known benefits of maintaining healthy hair, skin and nails, and for calcium absorption in the early stages of bone formation, silica is needed for flexible arteries, and plays a significant role in the prevention of cardiovascular disease.