fefjj

Inner Mongolia

07:07, 2011-Nov-2 .. 0 comments .. Link

Jewelry purchase
Topaz ( 1) choose Topaz should first pay attention to color, pure and fresh wine yellow, orange topaz is to share.

( 2) the gem processing should be standardized and bright, no *****s, defects or edge collapse.

( 3) should be asked about color is natural or radiation change color.
[ ] theory of crystal chemistry composition ( wB% ): according to Al2 [SiO4 ] ( OH ) 2, SiO2 33.4, Al2O3 56.6, H2O 10; F can replace OH, theoretical content of 20.65%. F : OH = 3 : 1 to 1 : 1, the topaz generating conditions vary: pegma***e type, the content of F close to the theoretical value; Yun Yingyan, the content of OH increased to 5 ~ 7%; hydrothermal type, F and OH similar content.

[ ] orthorhombic structure and morphology, A0 = 0.465nm, B0 = 0.880nm, C0 = 0.840nm; Z = 4. The crystal structure is composed of O2 -, F -, OH - ABCB layer 4 of the most compact, stacked layers (010 ). Al3 occupy eight surface voids, [AlO4 ( F, OH ) 2] eight surface connected with the body [SiO4] tetrahedron.

The double cone crystal cl***, D2h-mmm ( 3L23PC ). Columnar crystal. Common form: m, l, J trapezius column, trapezius double cone n, O, P, Q, C, B parallel sided. Cylinder Chang Youzong lines. Often irregular granular, m***ive aggregate.
[ physical ] colorless or microstrip blue green, yellow, white, brown or red yellow. Transparent. Vitreous luster. Cleaves completely. The hardness of 8. The relative density of 3.52 ~ 3.57.

Polarized light microscopy: colorless, uniaxial crystal ( two ). 2V = 44 ~ 66?, Ng = 1.616 ~ 1.644, Nm = 1.609 ~ 1.637, Np = 1.606 ~ 1.635. Interference color is low, usually for cl*** I fly ash - yellow.

[ occurrence and combination] produced mainly in granite pegma***e, Yun Yingyan and high temperature hydrothermal veins.

Identification characteristics of columnar crystal [ ], a rhombus, cylindrical surfaces are vertical stripes, cleaves completely, high hardness. This can be compared with similar quartz phase difference.

Industrial application ] transparent color beautiful crystal can be used as a gemstone, a topaz, is a semi-precious stone. Deep red "quality best, price is expensive; followed by pink, blue and yellow; colorless value minimum. Can be used for grinding materials, precision instrument bearing etc..

Topaz is in high temperature and volatile components under conditions of formation, is a typical gas hydrothermal mineral, found in granitic pegma***e, acidic volcano rock hole, Yun Yingyan and high temperature hydrothermal tin and tungsten in quartz veins. Transparent color beautiful topaz is high-grade gem materials. Brazil is the world's quality Topaz origin, discovered in Brazil in 1940 a Topaz crystal, weighing 240.25 kg, is clear and transparent, flawless.

Russia Ural and Pakistan by Carter Lang production because of containing Cr and a rose red topaz. The vast majority of the world's topaz is produced in the Brazil granitic pegma***e, including various color varieties, the largest weighing 117kg crystal. In addition, the United States, Burma, Sri Lanka, Ural mountains, Australia and other countries also have gem Topaz output.

Our topaz is produced to be produced in Inner Mongolia, Jiangxi, Xinjiang. In seventeenth Century, king of Portugal on the crown of Braganza diamond (1640 carats ) was considered to be the largest diamond, now has confirmed it is a colorless topaz.


Leave a Comment

{ Last Page } { Page 31 of 60 } { Next Page }

About Me

Home
My Profile
Archives
Friends
My Photo Album

Links

travel chengdu
giants pandas
Mr. Mckenic

Categories


Recent Entries

LED lighting performance
the investors
the temperature
market slowdown
brain informatio

Friends

Find quality Products, Trade Leads,
Manufacturers, Suppliers, Buyers and Wholesalers. Free Trade Blog