JPS58167495A - Synthesis of artificial beryl single crystal - Google Patents

Abstract

PURPOSE:To obtain high-quality artificial beryl single crystal efficiently and inexpensively, by blending BeO with Al2O3, SiO2, etc. in a given ratio, adding cesium element and a solvent to the blend, heating it to form a molten salt, annealing it so that a crystal is grown. CONSTITUTION:BeO is blended with Al2O3 and SiO2 approximately in a beryl composition ratio, and, if necessary, a colorant such as chromium oxide, etc. is added to it. To the prepared raw material substance is added a solvent selected from lithium molybdate, molybdenum dioxide, vanadium pentoxide, etc., stress in the growing crystal is released, in order to prevent the occurrence of cracks, cesium element is previously added to the solvent. The blend is heated to a temperature >= the melting point of the solvent to form a molten salt, after a given time, a beryl seed crystal is added to the salt, which is annealed to grow an artificial beryl single crystal. The prepared single crystal is used as a jewel such as emerald, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for synthesizing an artificial beryl single crystal using a solvent (7 lux), and more specifically to a method for efficiently and economically synthesizing beryl single crystals of better quality than molten salt. be.

The demand for single-crystal beryl, represented by emerald, has been increasing in recent years. Hydrothermal methods and molten salt methods using FM agents are known as methods for synthesizing carpenter beryl, but the present invention
This belongs to an improvement of the molten salt method.

The molten salt method shows the composition ratio of beryl, beryllium oxide, aluminum II oxide, 8-yetum, and silicon dioxide (as required, tetramuth oxide and nickel oxide, iron oxide, copal oxide). Add one or more solvents selected from vanadium pentoxide, lithium molybdate, molybdenum trioxide, etc. as a solvent to the raw material consisting of manganese and other auxiliary colorants or doping agents, and melt the above solvent. Beryl is added to the molten salt by heating it above temperature to form a molten salt, and then holding the molten salt at a constant temperature for a long time, or by holding it for a certain period of time and gradually cooling it with a gentle concentration gradient. This is a method of generating or growing artificial beryl around seed crystals by arranging them.

In this way, the molten salt method uses temperatures above the melting point, usually 700°C to 1200°C.
Although it can be produced or grown in the temperature range of ℃, in order to grow a high-quality beryl single crystal that does not contain inclusions in the crystal, there are several controls such as the temperature profile of the crucible furnace, growth speed, and the mm of solvent. There is India. In addition, there are two main types of Incluge capes: those that incorporate molten salts, namely, those that incorporate molten salts, and those that incorporate crystalline capes that are produced in the same crucible as 7-enayaite in the same way as beryl. This is the main cause of the decrease in transparency, which is the most important point in jewelry. These include.

This is unavoidable at this stage in the synthesis of artificial beryl single crystals by the molten salt method, and this is the biggest problem in terms of the quality of artificial beryl single crystals. why feather
The cause of occurrence of inclusion cracks is that dislocation occurs during crystal growth, resulting in distortion, and when it reaches a certain point, the distortion releases.The released part becomes a beam rack, and cracks occur. This is due to the inflow of 7 lux into the part, which causes feather inclusion damage.The way to suppress cracks is to control the growth speed and prevent the occurrence of inclusion carbon by adding a strain release agent. Can be done. The present invention is characterized in that cesium is added to the solvent in order to relieve stress and prevent the occurrence of cracks.In order to further clarify the effects of the present invention, Examples are included. Example 1 (1) Raw material, solvent, and blended beryl powder 10F VxOi 100 f MOon 10 Of LitMOO Hatake 100 f yH8・3t OrlOl (L 2 f) (2) Apparatus and method The above materials were placed in a platinum crucible. For filling and heating, the temperature was raised to 950° C. using the apparatus shown in FIG. 1, and 24 hours after the temperature reached 950° C., seed crystals were put in, and then taken out and observed after sunset.

(3) As a result, a good quality product was obtained in which the beryl single crystal had grown from 2 to 5 cm and no inclusion defects were observed.

Example 2 (1) Raw material, solvent, and formulation Same as Example 1 (Z) Apparatus and method 950°C temperature increase 24 hours later, seed crystals were added and then slowly cooled to α1°C/Hrasoc (3) Results Same implementation as Example 1 Examples & (1) Raw material, solvent and blended beryl powder 10F vlol 500? Lion 50 f NH8 30 f OrlOl (L 2 f(z) Apparatus and method Same as Example 1 (II) Result Beryl single crystal grows 2~5 m.

As a special feature, a high-quality single crystal was obtained without any inclusion defects due to the large growth of atlwiJ-.

In the present invention, it is also possible to use other solvents and complementary color agents other than those in the examples, and these can be selected without being limited to the scope of the examples of the present invention.

As understood from the above examples, according to the present invention, by adding cesium to the solvent used to synthesize artificial beryl single crystals, the quality can be improved while retaining the essential benefits of the conventional molten salt method. The present invention is extremely meaningful as a method for producing artificial beryl single crystals, since the yield can be improved and costs can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 shows the heating device used in the present invention and the layout inside the nut. Explanation of symbols> 1... Heating device 2... Heater 3... Platinum crucible 4... Seed crystal 5... Molten salt
6...buckle and above Figure 1

Claims (1)

[Claims] Lithium molybdate, molybdenum dioxide, vanadium pentoxide, etc. as a solvent are used as a solvent to a raw material obtained by adding beryllium oxide, aluminum #I, silicon dioxide, and other colorings such as chromium oxide as necessary. Adding cesium element to the above solvent in a method of synthesizing or growing an artificial beryl single crystal by adding one or more selected from among them and heating it above the melting temperature of the above solvent to form a molten salt. A method for synthesizing an artificial beryl single crystal by a molten salt method, which is characterized in that the beryl single crystal is synthesized or grown.