User:Bren bri/sandbox

=Introduction= Danbaite is a metallic mineral with chemical and empirical formula of CuZn2. It was discovered in non-magnetic fraction originated from Cu-Ni sulfide deposit in Southwest China. The mineral is characterized as being in very small aggregates that range from 0.05-0.2 mm.Because Danbaite is associated with the X-ray features for native chromium, it shows that Danbaite and native chromium are derived from natural new-mineral species.

=Structure= Danbaite has been analyzed quantitatively using two different samples containing pure copper and zinc. Selecting a basis of 3 atoms, the results from table 1 correspond to CuZn1.9574 and CuZn2.016.X-ray powder diffraction is a quick way to identify the phase of a crystalline materials and its unit cell dimension. The Danbaite grains were obtained by selecting heavy artificial mineral concentrates. The camera phi was set to 57.3 mm, under that condition, the pattern of the powder was recorded. The lines of the X-ray powder diffraction of Danbaite were indexed on a cubic cell. In order to determine the cell dimensions of the cubic lattice, the variable scale method was utilized. The dimension of a is 7.7615 Å and the volume of the cell V=467.55 Å^3, and Z=32 (Zn, Cu). Synthetic- γ  has a equals to 8.860 Å and a volume of    695.51 Å^3 with Z equal to 4. The alloys of the copper-zinc system have six phases which are γ, β, η, ε, α, δ. Those faces can be categorized into homogeneous primary solid solution and electronic compound which is electron number /atomic number every time it reaches a particular number such as 3/2(β-phase). Electron compound is also known as electron concentration. In the α-phase,the copper atoms and the zinc atoms exchange in the Cu lattice and create a type of primary solid solution. It has a copper-like texture and has a face-centered cubic lattice. At every phase, the new lattice does not resemble the lattice of the original element. This trend characterizes the chemical compound composed of metals. The distribution of atoms in the compound are not displayed in a ordered manner. As the temperature increases, the two elements do not occupy the same site. Thus, the electron compound is assumed to be intermediate members among the solid solutions and chemical compound. One the temperature decreases, atoms are distributed in order.In the β-phase,the Cu-Zn are composed of 36.5 to 46% of zinc. The alpha and beta solid solution take place during equilibrium. The zinc atom is positioned at body centered and the copper are located at the corner. The arrangement of atoms is in order at less than 453 degrees.In theγphase,the electron concentration of Cu-Zn is 21/13. After crystallization, the compound forms a unite cell with 52 atoms.The lattice type is complex cubic. The atomic arrangement is in order at 270 degrees.In the ε-phase,the phase occurs when the electron atom ration is 7:4.The zinc crystals which are hexagonally packed are formed during crystallization. The ration of valence electron of Danbaite relative to the atom is 5:3

=Physical Properties= The mineral has no cleavage and with a good metallic luster. Using binoculars, it tends to look silverish-white. However, under a reflected microscope, it is white with a tint of blue. It does not have any internal reflections and twinning. But it is isotropic. The Vickers hardness number for danbaite averages to 267 kg/mm^2 which correspond with 4 on the Moh’s hardness.According to Chen, the fact that the chromaticity coordinates of the color, X=0.3364, Y=0.3261, the dominant wavelength color=-519, the purity of the color is 0.0304 are all proof that danbaite can also be white.

=Geological Occurences= The discovery of Danbaite occurred in a platinum-bearing sulfide deposit that can be found in an ultramafic intrusion sheet in the Carboniferous Daxue Group on the axis where the plunged anticline is located.Harzborgite, gabbro and lherzolite make up the intrusion. Danbaite has an upper rock composed of carbonaceous slate, sericite-quartz-schist and thin marble. The lower country rock is composed of marble and quartzite. The ore bodies mainly occur in serpentinized and steatitized harzborgite of the lower middle part of the ultramafic intrusion. The ore bodies are from scattered, compact and taxitic types. Danbaite is formed in massive ore by the contact zone. It is botryoidal and spherical aggregates that ranges from 0.05-0.2 mm with a diameter ranging up to 0.15mm and also in thin film which is thick around native chromium. The minerals that are associated with Danbaite are pyrrhotite, pentlandite, chalcopyrite,violarite, cubanite,bornite,sphelerite,galena, linnaeite, magnetite with minor testibiopalladite, subburyite, sperrylite, omeiite ,gold and electron.