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Natural fluorite mineral has ornamental and lapidary uses. Fluorite may be drilled into beads and used in jewelry, although due to its relative softness it is not widely used as a semiprecious stone. It is also used for ornamental carvings, with expert carvings taking advantage of the stone's zonation.
The main uses of fluoride, in terms of volume, are in the production of cryolite, Na 3 AlF 6. It is used in aluminium smelting. Formerly, it was mined, but now it is derived from hydrogen fluoride. Fluorite is used on a large scale to separate slag in steel-making. Mined fluorite (CaF 2) is a commodity chemical used in steel-making.
The word "fluorine" derives from the Latin stem of the main source mineral, fluorite, which was first mentioned in 1529 by Georgius Agricola, the "father of mineralogy". He described fluorite as a flux—an additive that helps melt ores and slags during smelting. [1] [2] Fluorite stones were called schone flusse in the German of the time ...
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 ...
Yttrocerite is a variety of the mineral fluorite with a chemical formula Ca F 2 +(Y,Ce)F 3. It is bluish red with isometric crystals and is named for the yttrium and cerium it contains. It has a Mohs hardness of 4–5. It has been found in Sweden, several states in the United States and Norway. [1]
The fluoride minerals containing essential yttrium include tveitite-(Y) (Y,Na) 6 Ca 6 Ca 6 F 42 and gagarinite-(Y) NaCaY(F,Cl) 6. Sometimes mineral fluorite contains admixtures of yttrium. [ 1 ] [ 2 ]
Food rotation is important to preserve freshness. When food is rotated, the food that has been in storage the longest is used first. As food is used, new food is added to the pantry to replace it; the essential rationale is to use the oldest food as soon as possible so that nothing is in storage too long and becomes unsafe to eat. Labelling ...
[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.