SU1403784A1 - Method for identification of luminescent minerals - Google Patents

Abstract

The invention relates to the field of research on the chemical or physical properties of substances. The goal is to increase the accuracy of analysis and expand the range of defined minerals. The method is emitted by irradiating the sample under investigation with a UV laser with a density of 0.5 MW / cm or more, luminescence is detected in the yellow region of the spectrum. The lush intensity intensities are measured after 10 and 10 s after excitation of the luminescence. Oired from the difference of the measured intensities, compare it with the same value for Ztalon and identify cassiterite. 1 il. . 1 (L

Description

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The invention relates to the field of the investigation of the chemical or physical properties of substances, in particular to the study of the mineral properties of minerals, and can be used in prospecting and evaluation work on tin and in the enrichment of cassiterite ores.

The aim of the invention is to increase the accuracy of the analysis and broaden the range of detectable minerals by detecting cassiterite.

The drawing shows the oscillogram of the luminescence intensity of the rock specimen.,

The essence of the proposed method is as follows.

The exposed surface of the wall of the mine workings, pieces of ore, rock samples, grain or polished sections, technological conversion products with arbitrary size and shape are irradiated. A 1-laser radiation of an AL-202 nitrogen laser (-337 ni, excitation density per pulse 0.5 bW / cm) for the time required to observe the impressed light, with luminescence, in which the intensity of the luminescence is measured. After a time of 10 s (1), the intensity of the luminescence is measured; after a time of 10 (I,) j, the difference in the measured intensities (1, -1,) is determined. The obtained value is compared with a similar product for the standard, for which artificial mixtures are used that contain cassiterite and a side of the D1y molybdoshee 1pcs, and. cassiterite is detected,

PRI me R 1. A rock sample from the Trudovoye deposit (KirgSSR) with a size of 30 x 30 ohm was analyzed using an ultraviolet laser of the AL-202 type (l 337 km, P "0.5 MW / cm, f 10 Hz , “7 not) excite in it a luminescence, emit a yellow glow through a set of light filters BS - 8 and ZhSS-17, which focuses the PMT-100 (voltage on the photomultiplier 1800.V) and with Pom) Yu oscilloscope of the type C1-65 L measure the intensity of the lux {inescence through the lifetime of the excited state 10 C (1j 100 srv., Unit) and after 10 s ("

 20 uel, ed,). The difference of the measured intensities 1, is determined. equal to 80 yen. unit "This value is compared with the analogous value

for reference and judge on the presence in the sample of cassiterite So I, - 1, is equal to 80 arb. units, when compared with the reference, is 10, which corresponds to the presence of cassiterite in the sample — 10%.

The mineralogical analysis of the sample under study confirms the presence of cassiterite and molybdosheelite in it in a ratio of 1: 8.

A controversial analysis of the proposed method and prototype shows that, when analyzing this sample, according to the prototype method, the luminescence spectra under steady-state conditions and with the time lag are the same, and the change in luminescence intensity was practically undetectable, so cassiterite was not determined.

EXAMPLE 2 An artificial mixture of zircon, molybdosheelite, and cassiterite is irradiated with an LGI-21 UV laser (/ 337 nm, P 0.01 MW / cm2, 10 Hz, T-7 n). The analysis of the yellow luminescence excited during this period (spectrum,) shows that only zircon and molybdumolite luminesce, while cassiterite does not excite. with . With the help of an optical system, by focusing a laser beam, the excitation density is gradually increased. At P 0,2 0.2 Pcs / ck, the analysis of the excited yellow glow (spectrum,) indicates that the glow of cassiterite begins to be fixed, but at the same time the intensity of luminescence of identical zircon and molybdosheelite centers exceeds the intensity of cassiterite's pomiteral intensity. As the excitation density increases further, the laser beam focuses on the intensity of the luminescence of cassiterite, which increases significantly faster than the luminescence intensity of zircon and molybdosheelant, and at P 0.5 MW / cm they compare. A further increase in P no longer leads to a significant increase in signals (both are in the saturation region). An earlier saturation of zircon is associated with the fact that it has impurity centers of luminescence, and its own cassiterite.

Thus, the analysis according to the proposed method is possible only when the excitation density in a pulse is i MW / cm.

Claims (1)

Formula iso-bretenn A method for identifying luminescent minerals, comprising sample is irradiated with a UV laser, luminescence is detected in the yellow region of the spectrum, measures its characteristics, is compared with a similar value for the standard, and identifies the Mimepan under investigation, characterized in that analyzing and expanding the range of detectable minerals due to the detection of casit seritat, an ultraviolet laser with a density of 0.5 MW / cm is used to excite luminescence and more than 5 lumenscent intensities are measured 10 and 10 s after the occurrence of luminescence, That difference in the measured intensities compares it to the same magnitude for ztapon and identifies cassiterite. Tfrffs}