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Blue sapphire of gem quality was recently discovered in spinel–chlorite–muscovite rock within meta-ultramafites near the Ilmenogorsky alkaline complex in the Ilmen Mountains of the South Urals. More than 20 minerals were found in the assemblage with the blue sapphire. These sapphire-bearing rocks are enriched in LREE and depleted in HREE (with the negative Eu anomalies) with REE distribution similar to those in miascites (nepheline syenite) of the Ilmenogorsky alkaline complex. 87Sr/86Sr ratios in the sapphire-bearing rocks varied from 0.7088 ± 0.000004 (2σ) to 0.7106 ± 0.000006 (2σ): epsilon notation εNd is −7.8. The Rb-Sr isochrone age of 289 ± 9 Ma was yielded for the sapphire-bearing rocks and associated muscovite. The blue sapphires are translucent to transparent and they have substantial colorless zones. They occur in a matrix of clinochlore-muscovite as concentric aggregates within spinel-gahnite coronas. Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) analyses showed values with trace elements typical for “metamorphic” blue sapphires, with Ga/Mg < 2.7, Fe/Mg < 74, Cr/Ga > 1.5 (when Cr is detectable), and Fe/Ti < 9. Sapphires overlap “metasomatic” at “sapphires in alkali basalts” field on the FeO–Cr2O3–MgO–V2O3 versus FeO + TiO2 + Ga2O3 discriminant diagram. The sapphires formed together with the spinel-chlorite-muscovite rock during metasomatism at a contact of orthopyroxenites. Metasomatic fluids were enriched with Al, HSFE, and LILE and genetically linked to the miascite intrusions of Ilmenogorsky complex. The temperature required for the formation of sapphire–spinel–chlorite–muscovite rock was 700–750 °C and a pressure of 1.8–3.5 kbar.

The paper summarizes the data on mineral assemblages, crystal morphology and chemical composition of zeolites (analcime, natrolite, gonnardite, paranatrolite, scolecite, mesolite, garronite-Na, phillipsite-K, harmotome, chabazite-Ca, heulandite-Ca, heulandite-Sr, heulandite-K, stilbite-Ca,brewsterite-Sr and, probably, cowlesite) from zeolite-bearing pegmatites and late veinlets, which are located in miaskites of the NW contact of the Vishnevogorsky block and Sedlovidnaya miaskite block, which host vein ore bodies of the Vishnevogorsky Nb deposit at the South Urals. Garronite-Na is found for the first time in Russia and this is the second finding in the world. Some zeolites (brewsterite-Sr, heulandite-K, heulandite-Sr, mesolite, and phillipsite-K) are identified for the first time in the Vishnevye Mountains. Figures 21. Tables 1. References 14. Key words: zeolites, Vishnevye Mountains, South Urals

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ОсОбеннОсти сОстава ОснОвных пОрОдООбразующих минералОв амфибОлитОв ильменскОй серии ильменОгОрскОгО кОмплекса (южный урал) А. С. Ниêàíäðîâ, С. Н. НиêàíäðîâИльмеíñêèй гîñóдàрñòâеííый çàпîâедíèê, Ìèàññ nik@ilmeny.ac.ru В ðàбîòå пðèвåдåíы ðåзóëьòàòы èзó÷åíèя ðàзëè÷íых òèпîв àìфèбîëèòîв, пðîñòðàíñòвåííî ñîвìåщåííых в пðåдåëàх èëь-ìåíñкîй ñåðèè èëьìåíîãîðñкîãî кîìпëåкñà (Южíый Óðàë). В ñîñòàв ñåðèè вхîдяò ðàзëè÷íыå àìфèбîëèòы (дî 80 % îò îбщåãî îбъёìà), пëàãèîãíåйñы бèîòèòîвыå, ãðàíàò-бèîòèòîвыå, дèîпñèд-ñкàпîëèòîвыå пîðîды, ðàзëè÷íîй ìîщíîñòè ãðàíèòíыå дàйкè è пåãìàòèòîвыå òåëà. Èëьìåíñкàя ñåðèя явëяåòñя îдíîй èз вàжíых ñòðóкòóðíî-вåщåñòвåííых ÷àñòåй èëьìåíîãîðñкîãî кîìпëåк-ñà. Èññëåдîвàí ìèíåðàëьíый ñîñòàв àìфèбîëèòîв, èзó÷åíы îñîбåííîñòè îñíîвíых пîðîдîîбðàзóющèх è вòîðîñòåпåííых ìèíåðà-ëîв (àìфèбîëы, пèðîкñåíы, пëàãèîкëàзы, ñëюды è ò. д.). Àìфèбîëèòы ðàздåëåíы íà двå ãðóппы: ñ пèðîкñåíîì è бåñпèðîкñåíîвыå.Ключевые слова: èльìåíîгîðскèй кîìплåкс, èльìåíскàя сåðèя, àìôèбîлèты, сîстàв пîðîäîîбðàçóющèх ìèíåðàлîв.Compositional features major roCk-forming minerals of the amphibolites of ilmenskaYa series of ilmenogorskY Complex (the south urals) A. S. Nikandrov, S. N. NikandrovIlmen State Reserv, Miass nik@ilmeny.ac.ruThe paper were shows the results of the study of various types of amphibolites joint within "ilmenskaya series" of the ilmenogorsky complex (South Urals). This "series" is build up of amphibolites (up to 80 % of the total), biotite plagiogneiss, garnet-biotite rocks, diopsidescapolite rocks, granites dike and pegmatite of varying thickness. "Ilmenskaya series" is the important structural parts of the ilmenogorsky complex. The mineral composition of amphibolites were studied, features of composition of the major and minor rock-forming minerals (amphibole, pyroxene, plagioclase, mica and etc.) were analyzed. Amphibolites were separated for several groups: with and without piroxenes.Keywords: ilmenogorsky complex, ilmenskaya series, amphibolites, composition of the major rock-forming minerals. ВведениеИльмеíîгîрñêèй êîмплеêñ предñòàâляеò ñîáîй ñóáмерèдèîíàльíóю ñòрóêòóрó, ñлîжеííóю рàçлè÷-íымè мàгмàòè÷еñêèмè (щелî÷íымè, êèñлымè, îñ-íîâíымè è óльòрàîñíîâíымè) è меòàмîрфè÷еñêèмè пîрîдàмè (àмфèáîлèòы, гíейñы, êрèñòàллîñлàíцы). Пîñледíèе â âèде реçêî àñèммеòрè÷íыõ (дàйêîпîдîá-íыõ èлè плàñòîîáрàçíыõ) òел ñлàгàюò òîлщó, êîòîрàя яâляеòñя âмещàющей для òел мàгмàòè÷еñêèõ пîрîд. Òàêîе ñòрîеíèе меòàмîрфè÷еñêîй òîлщè длèòельíîе âремя îáъяñíялîñь ñ пîçèцèй мîíîцèêлè÷íîгî фîр-мèрîâàíèя êîмплеêñà çà ñ÷еò пàлеîçîйñêèõ îñàдî÷-íыõ òîлщ è ñîпрîâîждàлîñь пîпыòêàмè ñòрàòèфè-êàцèè рàçреçà. Вмеñòе ñ òем â õîде прîдîлжàющегîñя èçó÷еíèя êîмплеêñà пîяâлялàñь íîâàя èíфîрмàцèя, â êîрíе прîòèâîре÷àщàя дàííîй òрàêòîâêе: рàçрîç-íеííîñòь рàçреçîâ, òеêòîíè÷еñêèе грàíèцы пîдрàçде-леíèй, геîõèмè÷еñêèе дàííые, ñâедеíèя пî àáñîлюò-íîмó âîçрàñòó è дрóгèе. В ñîîòâеòñòâèè ñ âышепере-÷èñлеííым â пîñледíèе деñяòèлеòèя ñфîрмèрîâàлàñь êîíцепцèя, ÷òî èльмеíîгîрñêèй êîмплеêñ предñòàâ-ляеò ñîáîй регèîíàльíóю пîñòêîллèçèîííóю ñдâèгî-âóю çîíó, êîòîрàя ñфî...