{"id":46961,"date":"2026-02-08T09:02:07","date_gmt":"2026-02-08T08:02:07","guid":{"rendered":"https:\/\/www.ssef.ch\/?p=46961"},"modified":"2026-02-27T16:10:14","modified_gmt":"2026-02-27T15:10:14","slug":"visit-of-the-letseng-diamond-mine-in-lesotho","status":"publish","type":"post","link":"https:\/\/www.ssef.ch\/jp\/visit-of-the-letseng-diamond-mine-in-lesotho\/","title":{"rendered":"Visit of the Let\u0161eng diamond mine in Lesotho"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"46961\" class=\"elementor elementor-46961\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-18ac0dd2 e-flex e-con-boxed qodef-elementor-content-no e-con e-parent\" data-id=\"18ac0dd2\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-25b410d elementor-widget elementor-widget-text-editor\" data-id=\"25b410d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>In November 2025, Dr. Michael S. Krzemnicki and Dr. Michael Mintrone, Head of the Diamond Department at SSEF, were invited to visit the Lets\u030ceng diamond mine in Lesotho as part of a collaboration project.<\/p><p>The Lets\u030ceng diamond mine is known for its large diamonds of exceptional quality and is the highest diamond mine (at 3200 m altitude) in the world. Located in a remote part of the highlands of Lesotho, already the access to the mine is adventurous along a steep and winding road passing by the nearby AfriSki ski resort, which is the only one on the African continent.<\/p><p>During our stay at the diamond mine, we were impressed to get privileged access not only to the deep open mining pipes and to kimberlite samples, but also to the high-density mineral sorting unit and the high-security diamond recovery unit. Luckily, we were able to see some of the outstanding diamonds recovered in the past two months at the Let\u0161eng mine. The tour was concluded with a visit to a primary school in a nearby village and a poultry station, two of the many local projects supported by Let\u0161eng diamonds.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-cd1b6b5 elementor-widget elementor-widget-image\" data-id=\"cd1b6b5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/Letseng-diamond-mine.jpg\" class=\"attachment-large size-large wp-image-46991\" alt=\"\" srcset=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/Letseng-diamond-mine.jpg 1024w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/Letseng-diamond-mine-300x225.jpg 300w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/Letseng-diamond-mine-768x576.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 1: Arrival at the Let\u0161eng diamond mine in the remote highlands of Lesotho. Photo: M.S. Krzemnicki, SSEF.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-54bc2d1 elementor-widget elementor-widget-image\" data-id=\"54bc2d1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"1024\" height=\"766\" src=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_2.jpg\" class=\"attachment-large size-large wp-image-46997\" alt=\"\" srcset=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_2.jpg 1024w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_2-300x224.jpg 300w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_2-768x575.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 2: The open pit mining at the main kimberlite pipe at Let\u0161eng. The greenish rock is the kimberlite still to be excavated in the coming months and years. Photo: M.S. Krzemnicki, SSEF.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-8ea4bad elementor-widget elementor-widget-image\" data-id=\"8ea4bad\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_3.jpg\" class=\"attachment-large size-large wp-image-47003\" alt=\"\" srcset=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_3.jpg 1024w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_3-300x225.jpg 300w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_3-768x576.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 3: Dr. Michael Mintrone holding two exceptional rough diamonds at Let\u0161eng diamond recovery unit. Photo: M.S. Krzemnicki, SSEF.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bcb98f1 elementor-widget elementor-widget-image\" data-id=\"bcb98f1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_4.jpg\" class=\"attachment-large size-large wp-image-47009\" alt=\"\" srcset=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_4.jpg 1024w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_4-300x225.jpg 300w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/306_Fig_4-768x576.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">Figure 4: The sorting and recovery units of the Let\u0161eng diamond mine at dawn. Photo: M.S. Krzemnicki, SSEF.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-774d805 elementor-section-boxed elementor-section-height-default elementor-section-height-default qodef-backgound-letter-holder-no qodef-elementor-content-no\" data-id=\"774d805\" data-element_type=\"section\" data-e-type=\"section\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-extended\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-c864454\" data-id=\"c864454\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-b30f741 elementor-widget elementor-widget-text-editor\" data-id=\"b30f741\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<h2>Want to learn more about diamonds?<\/h2>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f3353f1 elementor-widget elementor-widget-image\" data-id=\"f3353f1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"900\" height=\"742\" src=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2023\/09\/DIAMOND-footer-jpeg.webp\" class=\"attachment-large size-large wp-image-34585\" alt=\"\" srcset=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2023\/09\/DIAMOND-footer-jpeg.webp 900w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2023\/09\/DIAMOND-footer-jpeg-300x247.webp 300w, https:\/\/www.ssef.ch\/wp-content\/uploads\/2023\/09\/DIAMOND-footer-jpeg-768x633.webp 768w\" sizes=\"(max-width: 900px) 100vw, 900px\" \/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-bf989bf\" data-id=\"bf989bf\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-e0cf775 elementor-widget elementor-widget-text-editor\" data-id=\"e0cf775\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<h4>Start your journey to becoming a diamond expert with our free online course &#8220;Introduction to diamonds&#8221;.<\/h4><p>Learn all about diamonds. Their fascinating history, how they form, where they come from. Learn about all the different origins of diamonds and their treatments. Take this course as an introduction to the wonderful world of diamonds.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7d76145 elementor-widget elementor-widget-laurits_core_button\" data-id=\"7d76145\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"laurits_core_button.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<a class=\"qodef-shortcode qodef-m qodef-button qodef-layout--filled qodef-html--link\" href=\"https:\/\/www.ssef.ch\/masterclass\/diamond-en\/\" target=\"_self\"  >\n\t<span class=\"qodef-m-text\">Discover the FREE course<\/span>\n<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-656818d elementor-widget elementor-widget-spacer\" data-id=\"656818d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"spacer.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-spacer\">\n\t\t\t<div class=\"elementor-spacer-inner\"><\/div>\n\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-7657c0a elementor-widget elementor-widget-text-editor\" data-id=\"7657c0a\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>You can also discover our Basic Diamond in-person course<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-dc12617 elementor-widget elementor-widget-laurits_core_button\" data-id=\"dc12617\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"laurits_core_button.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<a class=\"qodef-shortcode qodef-m qodef-button qodef-layout--textual qodef-html--link\" href=\"https:\/\/www.ssef.ch\/courses\/basic-diamonds\/\" target=\"_self\"  >\n\t<span class=\"qodef-m-text\">Basic Diamond Course<\/span>\n<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>In November 2025, Dr. Michael S. Krzemnicki and Dr. Michael Mintrone, Head of the Diamond Department at SSEF, were invited to visit the Lets\u030ceng diamond mine in Lesotho as part of a collaboration project. The Lets\u030ceng diamond mine is known for its large diamonds of exceptional quality and is the highest diamond mine (at 3200 [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":46980,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[626],"tags":[725,742],"library_category":[],"library_author":[],"class_list":["post-46961","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-blog","tag-diamond","tag-gemmology"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Visit of the Let\u0161eng diamond mine in Lesotho - SSEF<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ssef.ch\/visit-of-the-letseng-diamond-mine-in-lesotho\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Visit of the Let\u0161eng diamond mine in Lesotho - SSEF\" \/>\n<meta property=\"og:description\" content=\"In November 2025, Dr. Michael S. Krzemnicki and Dr. Michael Mintrone, Head of the Diamond Department at SSEF, were invited to visit the Lets\u030ceng diamond mine in Lesotho as part of a collaboration project. The Lets\u030ceng diamond mine is known for its large diamonds of exceptional quality and is the highest diamond mine (at 3200 [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ssef.ch\/visit-of-the-letseng-diamond-mine-in-lesotho\/\" \/>\n<meta property=\"og:site_name\" content=\"SSEF\" \/>\n<meta property=\"article:published_time\" content=\"2026-02-08T08:02:07+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-02-27T15:10:14+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ssef.ch\/wp-content\/uploads\/2026\/02\/Letseng-diamond-mine-Lesotho.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"600\" \/>\n\t<meta property=\"og:image:height\" content=\"338\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Laurent Cartier\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Laurent Cartier\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/\"},\"author\":{\"name\":\"Laurent Cartier\",\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/zh-hans\\\/#\\\/schema\\\/person\\\/c855f01c061d2c7b29f823eaee439288\"},\"headline\":\"Visit of the Let\u0161eng diamond mine in Lesotho\",\"datePublished\":\"2026-02-08T08:02:07+00:00\",\"dateModified\":\"2026-02-27T15:10:14+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/\"},\"wordCount\":368,\"publisher\":{\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/zh-hans\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.ssef.ch\\\/wp-content\\\/uploads\\\/2026\\\/02\\\/Letseng-diamond-mine-Lesotho.jpg\",\"keywords\":[\"Diamond\",\"Gemmology\"],\"articleSection\":[\"Research Blog\"],\"inLanguage\":\"jp\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/\",\"url\":\"https:\\\/\\\/www.ssef.ch\\\/visit-of-the-letseng-diamond-mine-in-lesotho\\\/\",\"name\":\"Visit of the Let\u0161eng diamond mine in Lesotho - 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