ROSE STONE
Name source
The word Rhodonite comes from the Greek word; it refers to the rose to symbolize its color. In Taiwan, it is also known as the rose stone.
Introduction
Rose stone, Rhodonite, also known as rose stone. Is a triclinic system.
chemical composition:
The chemical formula of the fluorite pyroxene is (Mn, Fe, Ca)·5[Si5O15], and the component often contains a certain amount of Ca. In addition to Fe2+, the Mn2+ ion can be replaced by Mg2+, and sometimes there is a trace amount of Zn2+. The chemical composition of rhodochrosite is calcium silicate ferromanganese Ca(Mn,Fe)·4[Si5O15].
The crystal belongs to the triclinic chain structure silicate mineral. It is homogenous to the three-spotted manganese phosgene. The rose sapphire does not belong to the pyroxene family, but a pyroxene mineral. The CaSiO3 component usually does not exceed 20%, and the Mg, Fe, and Zn isomorphisms are also common in place of Mn.
The rose phosgene in Xihu Village, Changping, Beijing, contains MgO higher, reaching 2.62%. It is a magnesium-rich variety and was once known as West Lake Village Stone. The rhodochrosite crystal is in the form of a thick plate or a column. Generally it is a granular or massive aggregate. Light pink to rose red, caused by Mn.
After the surface is oxidized, a black manganese oxide or hydroxide film is often produced. Glass luster. The three sets of cleavage are complete or medium, and the cleavage angles are nearly 90°. Moss hardness 5.5-6.5, specific gravity 3.4-3.75. Rhodochrosite is produced in many manganese deposits and is often associated with metasomatism.
The rhodomes formed by regional metamorphism are mostly manganese-rich and siliceous sediment reaction products. The fucaite formed by contact metamorphism is mainly produced by the contact between the acidic magmatic rock and the manganese-rich carbonate rock. Also found in Weijingyan and hydrothermal deposits. The dense block-shaped rose phosgene can be used as a material for carving art and craft.
specific gravity 3.4-3.7, hardness 5.5-6.5, the surface is susceptible to oxidation changes to manganese dioxide, reddish to pale yellow, no reaction under ultraviolet light. In the field, the mineral samples in the Hualien area were analyzed. The red part contained about 33% manganese and the black part was about 31%. The surface part was easily exchanged with iron and calcium. Rhodo is derived from the Greek rose.
The rose boulder is characterized by its characteristic rose red, obvious cleavage and high hardness. After weathering, there is a black oxidized fierce, which is also one of the characteristics. The difference from rhodochrosite is high hardness, no acid in case of acid.
Cause of occurrence
The sedimentary manganese ore layer is affected by regional metamorphism, or the rhodochrosite is exposed to contact and metamorphism to form rhodochrosite. It can also be produced in a manganese deposit that is caused by hydrothermal metasomatism. Occasionally there is also output in pegmatite. Occurred in metamorphic rocks or independent veins and deposits, sometimes associated with pyrolusite, feldsparite, calcite, quartz, etc. in iron deposits and manganese deposits. Most of them are sandwiched in quartz schist, mixed with brownish yellow and gray manganese feldspar, quartz and ferromanganese dolomite or rhodochrosite.
Rhodopsin is usually a product of metamorphism, found in rocks that contain manganese or are metamorphosed or exposed to metamorphosed rocks. It is symbiotic with calcium rosewood, rhodochrosite and garnet. Sometimes found in pegmatite and hydrothermal deposits, as lower temperature minerals coexist with other manganese minerals, sulfides, etc. Under the conditions of epigenetic conditions, the eucalyptus is easily oxidized and converted into pyrolusite and rhodochrosite. The result of hydration leads to the formation of water dimerite, silicomanganese or manganese-containing serpentine.
Place of origin
In addition to Beijing Xihu Village, the Chinese rose sapphire production area is also in the contact zone between the Hualixi period biotite plagiogranite and the Permian biotite and quartz schistite marble in Wangqing County, Jilin Province, and skarn. Type lead-zinc mine symbiosis. The rose stone is blocky and has a bright pink color. Shaanxi was found in the Shangluo area. The rose stone is rose red and pink. The texture is uniform and the engraving is good.
The Hallihad Mountain in Wulan County, Qinghai Province, is found in the Ordovician-Siluan slate, sericite slate, metamorphic sandstone and partially contacted altered rocks of the upper member of the Silurian Shaliuhe Group. It is symbiotic with calcium rose phosgene, manganese aluminum garnet, tremolite, epidote, zoisite and quartz. The rose meringue is pink, light yellow and colorless. The bougainvillea in Daliugou, Qilian County, Qinghai Province, has become a vein of varying sizes interspersed with iron-manganese siliceous rocks in the Middle Cambrian blue amphibole schist. In the Sichuan Province, Xinjiang Autonomous Region and other places, there are also the discovery of rose phosgene.
Among the world, the bougainvillea is mainly produced in the Harz Mountains of Germany, the United States, Australia, Romania, Brazil, the Urals of the former Soviet Union, Sweden, Mexico, Japan, South Africa and Tanzania. World famous places of origin are Plaifield in the United States, Langban in Sweden, Sverdlovsk in the Ural Mountains in Russia, and Broken Hill in New South Wales, Australia.
Parallel double-sided crystals, crystals are rare; mostly thick plate-like, sometimes three-dimensional isometric or one-way long. Common simplex: a(100), b(010), c(001), m(110), n(221), M(110), π(111), k(221), p(201), r (111), y (522), q (221). The crystal face is rough, the crystal edge is curved, and sometimes the polycrystalline twin crystal is formed according to (010). Granular or dense block aggregates.
Crystal structure
Crystal system and space group: triclinic system, space group C1i-P-1. Unit cell parameters: a0 = 9.758 angstroms, b0 = 10.49 angstroms, c0 = 12.205 angstroms, z = 2.
Powder crystal data: 2.772 (1) 2.924 (0.65) 2.98 (0.65).
In the crystal structure of the meringue, there are two double tetrahedrons [Si2O7] and a single tetrahedron [SiO4] coupled, infinitely repeating chain. Each siloxane tetrahedron and other tetrahedrons in the chain have two corner joints. The key extends in parallel (101) direction. The planes of the cations Mn, Ca, Mg, and Fe are alternately arranged with the oxygen ion plane.
There are five cation positions in the structure, in which MI, MII and MIII are six coordination; MIV is also six coordination, but because of a longer MO chain, it is close to 5 coordination; MV is not 7 matches of the rule. Obviously, MV favors the filling of large cation Ca and a few Mns than the other four positions; this also explains why the ratio of Ca ions and other cations (Mn, Mg, Fe) in the meringue is close to 1:4. Fe ions are most likely to enter the MI, MII, and MIII positions, followed by MIV, and MV is the most difficult.
Basic nature
1. The color is pale pink, rose red, the surface is often covered with oxidation, manganese hydroxide black veins.
2. Transparency is translucent to opaque.
3. Glossy glass to pearl luster.
4. Hardness 6.
5, density 3.50 (+0.26, -0.20) g / cm3.
6. The refractive index is 1.733-1.747, the birefringence is 0.010-0.014, and the point is 1.73.
7. Photonic biaxial crystal positive or negative.
8. Multi-color weak orange-red to maroon pleochroism.
9. Ultraviolet fluorescence is fluorescently inert.
10. The absorption spectrum is seen at 548 nm, and the narrow band is seen at 503 nm. The blue-violet region is generally absorbed.
Physical properties
Hardness: 5.5-6.5
Specific gravity: 3.56-3.57g/cm3
Cleavage: complete cleavage, the intersection angle is 92°30ˊ, and another (001) medium cleavage
Fracture: the fracture is not flat
Color: rose red to brown red, the surface is dim and black due to oxidation
Streak: gray or yellow
Transparency: transparent
Gloss: glass luster, sometimes pearlescent on the cleavage surface
Luminescence: none
Other: no soak in acid
Chemical properties
The blown flame burns, and the oxidized surface turns brownish black; the principle of repayment is melted into a red or brown vitreous. The reaction with manganese is mixed with the flux. Slightly soluble in hydrochloric acid to precipitate SiO2.