{"id":1683,"date":"2020-06-10T09:12:47","date_gmt":"2020-06-10T01:12:47","guid":{"rendered":"http:\/\/tg.zhongwei666.com\/?page_id=1683"},"modified":"2020-08-07T11:32:08","modified_gmt":"2020-08-07T03:32:08","slug":"thermal-treatment","status":"publish","type":"page","link":"http:\/\/www.iga-laboratory.com\/?page_id=1683","title":{"rendered":"Thermal Treatment"},"content":{"rendered":"\n\t

\n\t\t\t\t\tiga\n\t\t\t\t<\/h3>\n\t

\n\t\t\t\t\tthermal treatment\n\t\t\t\t<\/h2>\n

\n\t\tComing soon\n\t<\/h2>\n\t\t\t\t\t\t\t\t\tA Brief Discussion of the Optimization Treatment of Blue Sapphires\t\t\t<\/a>\n\t\t\t\tA Brief Discussion of the Optimization Treatment of Blue Sapphires\n\t\t\t\t\t\t\t

Abstract: Sapphire is the general name for corundum gemstones except for ruby. The main chemical component of sapphire is Al2<\/sub>O3<\/sub>. <\/sub>The blueness in sapphire is caused by a small amount of titanium and iron impurities.<\/p>\n

Keywords: blue sapphire, optimization, treatment, magnified observation<\/b><\/strong><\/p>\n

Blue sapphire is as precious as ruby. A small piece of blue sapphire can cost tens of thousands RMB if it has good color, luster, clarity and cut. However, the market is filled with treated blue sapphires, so you need to be cautious when purchasing them.<\/p>\n

1.<\/b><\/strong>Heat treatment<\/b><\/strong>\u00a0<\/b><\/strong>(<\/b><\/strong>enhancement<\/b><\/strong>)<\/b><\/strong>\u00a0<\/b><\/strong>\u00a0\u00a01.\u0e01\u0e32\u0e23\u0e40\u0e1c\u0e32 (\u0e01\u0e32\u0e23\u0e40\u0e1e\u0e34\u0e48\u0e21\u0e04\u0e38\u0e13\u0e20\u0e32\u0e1e)<\/b><\/strong><\/p>\n

Heat treatment is the most common way to optimize the blue sapphire. The change of temperature can control the color and improve the quality of the sapphire (enhance or lighten the color,\u00a0or remove unwanted color).<\/p>\n

Magnified observation :<\/p>\n

\u2460Solid inclusions may dissolve under high temperature and turn into smaller inclusions, resembling stains, spots, or threads<\/p>\n

\u2461Flaky or ringlike stress crackings may appear around some solid inclusions.<\/p>\n

\u2462Fluid inclusions may swell and flow into the new cracking\u00a0caused by the rupture.<\/p>\n

\"\"<\/p>\n

The picture is the heated blue sapphire. \u00a0Zircon is molten and the melt flows into the discoid cracking. As the temperature decreases, the melt recrystallizes, and small zircon crystals shaped like opaque ferns gather in the cracking(2)<\/sub>.<\/p>\n

The original color of Changle sapphire is usually black, but it can turn into a beautiful blue after heating. After heat treatment, blue color band of Shandong sapphire can turn transparent and colorless. Brown color band can turn blue. Sample without color band may show yellow color band after heating. Changle sapphires usually have prominent color bands, and one piece of sapphire usually has two colors. In most cases, Changle sapphires go through heat treatment (\u201cLaoshao\u201d\u00a0in jargon), rather than diffusion treatment.<\/p>\n

\"\"<\/p>\n

Fig. 2 Changle Sapphire<\/p>\n

\"\"<\/p>\n

Fig.3 Changle Multicolor Sapphires<\/p>\n

2.<\/b><\/strong>Surface d<\/b><\/strong>iffusion<\/b><\/strong>\u00a0treatment<\/b><\/strong>\u00a0<\/b><\/strong><\/p>\n

\u2460Diffused blue sapphire is usually in vivid blue or violet blue. Color is not uniform, concentrated on facets, lines, girdle and cracking (more easily observed\u00a0on the white paper or oil immersion).<\/p>\n

\u2461Fluorescent test. Some diffused blue sapphires show chalky blue or green fluorescence under short wave ultraviolet, while some show blue, green or even orange fluorescence under long wave ultraviolet.<\/p>\n

\"\"<\/p>\n

Diffusion Treated Blue Sapphire<\/p>\n

3.<\/b><\/strong>Irradiation treatment<\/p>\n

It is difficult to identify irradiated sapphires. However, irradiated yellow sapphires can be identified though its color stability, fluorescence, spectral absorption features and internal growth rings.<\/p>\n

4.<\/b><\/strong>Filling treatment<\/b><\/strong>\u00a0<\/b><\/strong><\/p>\n

When the sapphire is heated in oxygen, some materials (such as polymethyl\u00a0methacrylate) are filled into the cracking to conceal the blemishes, to improve the clarity and transparency, or enhance the color.<\/p>\n

\u2460Magnified observation: fillings of different shapes can often times be found inside, accompanied with flat air bubbles and colorful sparkles.<\/p>\n

\"\"<\/p>\n

Magnification of Cobalt Glass Filled Blue Sapphire<\/p>\n

\u2461Crackings turn red under CCF<\/p>\n

\"\"<\/p>\n

Cobalt Glass Fillings Under Natural Light<\/p>\n

\"\"<\/p>\n

Cobalt Glass Fillings Under CCF<\/p>\n","protected":false},"excerpt":{"rendered":"

iga thermal treatment Coming soon A Brief Discussion of …<\/p>\n

Thermal Treatment<\/span> \u67e5\u770b\u5168\u6587 »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-global-header-display":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":""},"_links":{"self":[{"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/pages\/1683"}],"collection":[{"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1683"}],"version-history":[{"count":7,"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/pages\/1683\/revisions"}],"predecessor-version":[{"id":2345,"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=\/wp\/v2\/pages\/1683\/revisions\/2345"}],"wp:attachment":[{"href":"http:\/\/www.iga-laboratory.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}