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Pure fluorite is colourless and transparent, both in visible and ultraviolet light, but impurities usually make it a colorful mineral and the stone has ornamental and lapidary uses. Industrially, fluorite is used as a flux for smelting, and in the production of certain glasses and enamels.
Fluoride was known to enhance bone mineral density at the lumbar spine, but it was not effective for vertebral fractures and provoked more nonvertebral fractures. [62] In areas that have naturally occurring high levels of fluoride in groundwater which is used for drinking water, both dental and skeletal fluorosis can be prevalent and severe. [63]
Though elemental fluorine (F 2) is very rare in everyday life, fluorine-containing compounds such as fluorite occur naturally as minerals. Naturally occurring organofluorine compounds are extremely rare. Man-made fluoride compounds are common and are used in medicines, pesticides, and materials.
Here is what you need to know about fluoridation of drinking water as a public health measure. Fluoride is a mineral that occurs naturally in water, soil and air that has been demonstrated to ...
The Casparian strip, a cell wall outside the stele but in the root, prevents passive flow of water and nutrients, helping to regulate the uptake of nutrients and water. Xylem moves water and mineral ions in the plant and phloem accounts for organic molecule transportation. Water potential plays a key role in a plant's nutrient uptake. If the ...
Many of these minerals are water-soluble and are often found in arid areas in crusts and other deposits as are various borates, nitrates, iodates, bromates and the like. Others, such as the fluorite group, are not water-soluble. As a collective whole, simple halide minerals (containing fluorine through iodine, alkali metals, alkaline Earth ...
[1]: 53 Pliny describes the mineral as having a "great variety of colours" with "shades of purple and white with a mixture of the two". [1]: 53 Whether this mineral was banded fluorite is uncertain, but it was apparently soft enough (like fluorite) to allow one particular man of consular rank to gnaw at the edges of his cup.
Fluorite, the primary mineral source of fluorine, which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb fluo meaning ' to flow ' gave the mineral its name. Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its ...