Datolite

Other Zircon ZrSi04, datolite CaBSi04(0Fl), danburite... 

Table 4.8. Concentrations of rare-earth elements in danburite and datolite (ppm)...

Datolite is caldiun borosilicate with a monoclinic structure (2/m) and space group P2i/c. It consists of superimposed complex sheets of linked oxygen and O, OH tetrahedra around silicon and boron atoms respectively the Si04 and B(0,0H)4 tetrahedra alternate, forming rings of four and eight tetrahedra. The natural datolite in our study consisted of seven samples from a variety of geologic environments. Concentrations of potential luminescence impurities in one sample are presented in Table 4.8. 

Fig. 4.16. a-d Laser-induced time-resolved luminescence spectra of datolite demonstrating Mn, Ce, Eu and Eu centers... 

The narrow band with two maxims at 335 and 360 nm in time-resolved emission spectra of datolite (Fig. 4.16a), with a short decay time of 30 ns is connected with Ce +. 

The narrow band at 455 nm with a decay time of 750 ns in the datolite luminescence spectrum belongs to Eu " luminescence (Fig. 4.16b), which was also detected by steady-state spectroscopy (Gaft et al. 1979). Besides that, narrow lines appear in the orange part of the spectrum with the main one at 610 nm (Fig. 4.16c) with a long decay time, which confidently may be ascribed to Eu ". ... 

Fig. 5.22. Luminescence and excitation spectra of in danburite and datolite (Gaft and Gorobets 1979)...

Characteristic bands of Mn + well studied by steady-state luminescent spectroscopy (Tarashchan 1978 Gorobets and Rogojine 2001) have been found in time-resolved luminescence spectra of calcite (Fig. 4.14a), fluorite (Fig. 4.10d), datolite (Fig. 4.16d), wollastonite (two bands at 555 and 603 nm Fig. 4.42a,c), and spodumen (Fig. 4.61a). 

Table 8.3. Results of datolite CaB(Si04)(0H) ore laseroluminescent sorting...

Fig. 8.4. a-d Time-resolved LIBS of datolite and danbiuite and gangue quartz and calcite... 

CFsli) anhydrite, calcite, feldspars, danburite, datolite, esperite, apophyllite, charoite, fluorite, hardystonite... 

Borax (tincal), kemite, colemanite, ulexite, probertite, hydroboracite, inderite, datolite, and szaibelyite (ascharite) are the only borate minerals of... 

Production of borax from the reaction of colemanite and sodium carbonate is carried out in Spain, Italy, and Poland. Turkish production from colemanite has been discontinued in favor of direct production from tincal ore. Sodium borates are produced in Russia from datolite and in Kazakhstan from szaibelyite. 

DATOLITE. Datolite. basic calcium boron silicate. CaBSi04(0H). occurs in monoclinic crystals of varied habit, mostly short stout prisms, but... 

Preparation and Uses. Boric acid can be prepared in the laboratory by acid hydrolysis of a variety of boron compounds, including halides, esters, salts, and hydrides. It is prodnced commercially by reactions of snlfinic acid with sodium borates in the United States, and with sodium and calcium borates in Turkey. In Sonth America, boric acid is prodnced by reaction of sulfuric acid with ulexite, a mixed sodium-calcium borate. Boric acid is also produced in Rnssia from the borosilicate mineral datolite. 

The main boric raw materials are boric acid H3BO3 and borax (Na2B4.07.10 H2O) or borax dehydrated to pentahydrate. Boron-containing natural raw materials have also been used in some instances they are based on the minerals datolite (2 CaO. ... 

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