Apatite
Apatite is not a mineral that is certain but the title of the number of minerals that includes Fluorapatite, Chlorapatite and Hydroxylapatite. Apatite is also a name that is generic to spell it out any of the three minerals which never have been specifically identified through analytical methods. Fluorapatite is definitely the most common of the three become used for gemstones but is generally referred to simply as “Apatite” within the gem trade. Fluorapatite is the fluorine (F) analogue of Chlorapatite, containing chlorine (Cl), and the water-rich (OH) Hydroxylapatite. It is difficult to tell the three apart and various amounts of fluorine, chlorine and water are present in mineral specimens that are most. Fluorapatite is also the phosphate (PO) analogue of Svabite. The three minerals of the series that is apatite also members of the Apatite Group of minerals that feature Mimetite, Pyromorphite, Svabite and Vanadinite.
Apatite is fairly common throughout the world and a modified form of Hydroxylapatite may be the main constituent of human bones and enamel that is dental. Apatite occurs in almost all stones which can be igneous is usually simply small disseminated grains or cryptocrystalline fragments. Large, well-formed crystals may be found in particular contact rocks that are metamorphic. Gem quality Apatite crystals are discovered in many places all over the world, including Brazil, Burma, Mexico and Madagascar.
Apatite gems can be found in colours of green, blue, violet, purple, pink, yellow, colourless and brown. Neon blue to apatite that is blue-green Madagascar is one of the rarest and most sought after colours. Blue cat’s eye Apatite from Brazil and Madagascar is also rarely available. Green Apatite has been called stone that is asparagus a bluish-green variety of Apatite originally found in Arendal, Norway was called moroxite. Apatite is an outstanding treasure whenever precisely cut although it is simply too soft for jewellery settings that are most. Apatite is the defining reference mineral for 5 on the Mohs scale of hardness. Apatite often exhibits bright yellow or blue fluorescence that is white UV light and may also be phosphorescent, especially the manganoan varieties. It is also strongly thermoluminescent at times.
Apatite was named in 1786 by German geologist Abraham Gottlob Werner (1749-1817), teacher of mineralogy and mining at the Freiberg Mining Academy, Germany. Werner named the mineral from the Greek word άπατάω (Epstein) meaning to deceive or even to be misleading because it was often confused along with other minerals such as Peridot and Beryl. The mineral that is specific Werner had described as Apatite was reclassified in 1860 as Fluor-apatite by the German mineralogist Karl Friedrich August Rammelsberg (1813-1899). Rammelsberg included the “Fluor-” prefix in allusion to the dominance of fluorine (F) within the composition. In 2008 Fluorapatite was renamed CaF that is apatite an article entitled “Tidying up Mineral Names: an IMA-CNMNC Scheme for Suffixes, Hyphens and Diacritical Marks” into the Mineralogical Record, vol. 39, no. 2 (March–April 2008), page 132, but this true name ended up being then reversed and renamed Fluorapatite by the IMA this season. Despite the renaming and naming, it is still many often called Apatite.
Some of the localities for fine crystals that are apatite: at Ehrenfriedersdorf, Saxony, Germany. From Untersulzbachtal, Salzburg, Austria. At Panasqueira, Portugal. From near Pech, Kunar Province, Afghanistan. At Chumar Bakhoor, Nagar, Gilgit District, Pakistan. In Brazil, at the Morro Velho gold mine, Nova Lima, Minas Gerais and at Currais Novos, Rio Grande do Norte. From Llallagua, Potosí, Bolivia. At Cerro de Mercado, Durango, Mexico. From the Pulsifer Quarry, Mt. Apatite, Auburn, Androscoggin County, Maine, USA. In Canada, large crystals from southeastern Ontario, as in Renfrew County, and in adjoining Quebec, that is Southwestern in Ottawa County, etc. An ore that is essential carbonatites; in Russia, in the Khibiny and Kovdor massifs, Kola Peninsula; through the Slyudyanka region, Lake Baikal, Eastern Siberia. At Phalaborwa, Transvaal, South Africa. From the Jacupiranga mine, São Paulo, as well as Tapir, Minas Gerais, Brazil. In the Mt. Weld carbonatite, 35 kilometres south of Laverton, Western Australia. At Ankarafa, Vohémar District, Sava Region, Antsiranana Province, Madagascar.
a 425-gram blue apatite natural gemstone rough
| Category: | Phosphate mineral |
| Chemical Formula: | Ca5(PO4)4F |
| Calcium Fluoro Phosphate | |
| Molecular Weight: | 504.30 gm |
| Composition: | Calcium | 39.74 % | Ca | 55.60 % | CaO |
| Phosphorus | 18.43 % | P | 42.22 % | P2O5 | |
| Oxygen | 38.07 % | O | |||
| Fluorine | 3.77 % | F | 3.77 % | F | |
| – % | F | -1.59 % | -O=F2 | ||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Hexagonal – Dipyramidal |
| Crystal Habit: | As prismatic hexagonal crystals, elongated on [0001], dominated by {1010} and {1011}, to 2 m; as complex tabular to discoidal crystals flattened on {0001}, typically with many forms; granular, globular to reniform, nodular, massive. |
| Twinning: | Rare contact twins on {1121}. Twin plane {1013} rare. Also twinning reported on {1010} and {1123}. |
| Cleavage: | Poor/Indistinct on {0001} and {1010} |
| Fracture: | Irregular/Uneven, Conchoidal |
| Tenacity: | Brittle |
| Mohs Hardness: | 5.0 (a Mohs hardness reference species) |
| Density: | 3.10 – 3.25 (g/cm3) |
| Optical Properties | Double refractive, uniaxial negative |
| Luminescence: | Often fluorescent; exhibiting bright yellow or blue-white fluorescence under UV light. May also be phosphorescent, especially the manganoan varieties. Also strongly thermoluminescent at times. |
| Radioactivity: | Not Radioactive |
| Colour: | Green, violet, purple, blue, pink, yellow, brown, white, colourless; may be zoned.Colourless or faintly tinted in thin section. |
| Transparency: | Transparent to Opaque |
| Lustre: | Vitreous to Sub-Resinous |
| Refractive Index: | 1.631 – 1.646 Uniaxial ( – ) |
| Birefringence: | 0.0020 |
| Dispersion: | Weak; 0.013 |
| Pleochroism: | Visible; weak to strong in coloured crystals |
| Ultraviolet Fluorescence: | Yellow Stones – purplish-pink, which is stronger in the long wave; blue stones – blue to light blue in both long and short wave; green stones – greenish-yellow, which is stronger in the long wave; violet stones – greenish-yellow in long wave, light-purple in short wave. |
