{"id":40139,"date":"2026-02-13T17:28:31","date_gmt":"2026-02-13T16:28:31","guid":{"rendered":"https:\/\/karmaka.de\/?p=40139"},"modified":"2026-02-13T17:28:32","modified_gmt":"2026-02-13T16:28:32","slug":"shock-origin-of-the-largest-ureilitic-microdiamond-structural-observations-and-%ce%b413c-value","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=40139","title":{"rendered":"Shock origin of the largest ureilitic microdiamond: structural observations and \u03b413C value<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>O. Christ, A. Barbaro, G. Bragaggia, S. Gross, E. Thomassot, M.C. Domeneghetti, M. Alvaro, F.E. Brenker, F. Nestola<\/p>\n\n\n\n<p>Geochemical Perspectives Letters V39, Published 13 February 2026<\/p>\n\n\n\n<p><a href=\"https:\/\/www.geochemicalperspectivesletters.org\/article2606\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><a href=\"https:\/\/www.geochemicalperspectivesletters.org\/documents\/GPL2606_SI.pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>PDF (OPEN ACCESS)<\/strong><\/a><\/p>\n\n\n\n<p class=\"justify-text\">&#8220;We report structural evidence for impact formed diaphite or stacking disorder in the largest known extraterrestrial microdiamond (&gt;300 \u03bcm) from the highly shocked ureilite Northwest Africa 6871. Shock indicators within the microdiamond indicate a diamond formation model during the catastrophic disruption of the ureilite parent body, rather than deep static processes. After removal of associated graphite, large geometry secondary ion mass spectrometry yielded \u03b413C\u2009=\u2009\u20132.89\u2009\u00b1\u20090.06 \u2030, an intermediate value in the range of ureilitic \u03b413C values. Combined with the Mg# of Northwest Africa 6871, the carbon isotopic signature shows that carbon was not affected by the impact which destroyed the ureilite parent body. Our findings therefore challenge the hypothesis that large ureilitic diamonds formed deep within their parent body and show that the carbon isotopes did not fractionate during diamond formation.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>O. Christ, A. Barbaro, G. Bragaggia, S. Gross, E. Thomassot, M.C. Domeneghetti, M. Alvaro, F.E. Brenker, F. Nestola Geochemical Perspectives Letters V39, Published 13 February 2026 LINK (OPEN ACCESS)PDF (OPEN ACCESS) &#8220;We report structural evidence&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[39],"tags":[250,1328,6359,245,1952,4205],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/40139"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=40139"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/40139\/revisions"}],"predecessor-version":[{"id":40140,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/40139\/revisions\/40140"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=40139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=40139"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=40139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}