| Th Dongping-type gold deposit is named after a gold deposit in Dongping villagewas explored, with its gold ores rich in tellurium (Te in abbrev.) and short of sulfides,which has been proven characteristic for all other gold deposits in the Shuiquangousyenite batholith on the northem margin of North China craton.T is 71ppm in maximum and 6.71 ppm in average, respectively for the gold oresand tends to concentrate in high-grade ores of gold bearing quartz veins. The quartzvein orebody is different from auriferous metasomated syenite orebody in correlationcoeffiency and the ratio between Te and Au, along with REE contenis: the former ishigher in Te, Au grades, in the value of Te/Au ratio (>0.7 in average), and lower inREE content (<10 ppm), whereas the latter is lower in Te abundance, in the value ofTe/Au ratio (<0.5) and higher in REE content (>20ppm). Te is in positive correlationwith gold both at depth and in horizon profiles of the quartz vein bodies, whosecorrelation coefficiency and the ratio between Te and An increase along with theincrease of An grade, suggesting that Te has the same concentrative center as of Auin the quartz vein orebody. In gold ores, Te presents as tellurides of Au, Ag, Pb inassociation with native gold, occurring in surfaces or/and fissures of galena, pyriteand quartz minerals. Therefore, Te and the 'refractory gold' are worth being extractedfrom these abundant tellurides.B ides the tellurides mentioned above that are common in gold deposits, Te isalso seen in such rare minerals as hessite, Au2Te and, a variety of unnamed telluritesand tellurates that may be subdivided into Au-bearing and Au free minerals. Theformer includes AtteO3, Au2TeO4, AuTeO4; and the latter schieffinilite, Zn2Te3O8,H2Pb2Fe4[TeO4]9.7-12H2O that were found by the author and are yet to be furtherstudied for acceptance by IMA-CNMMN as potential new minerals. Most of thesete1lurites and tellurates in these deposits are found to be products of coeval oxidationof calaverite, altaite and sufides, by Which 'refractory gold' of Au tellurides will bereleased as naive gold. Most native gold released through oxidation of tellurides,however, will be trapped in the telluraes or tellurites; or be combined by Te intellurites or tellurates, which prevent gold of hyPergene from secondaxy enrichmentunder the supergene oxidation environrnenis.Of the fOux metallogenic stages of two periods, Te was mineralized only at bothpyrite-qUartz stage and base metal sulfides quaftz stage, demonstrating itsunsustainable in time and confinement to a small area. From mineral associations ofnative gold -calaverite, ga1ena -altaite in conunon, and native silver-hessite at the endof the sulfides quartz stage, it is concluded that Te, fugacity is in 'unstheated statefor native Te' and will decline with the temperature of metallogeulc fluids decreased.It is inferred under observations on mineral paragenesis, modem geothermal fluids,and Te evaPoration experiments in nanometer scale particles, along with fluidinclusions and O,H,C,S isotope data that, Te, Pb, Au and parts of sulfides originatefrom deep under the crust during 'magtna degassing' and are transported in volatilefluids made of suspended nanometer scaled particles. ms high temperthee fluldsmixed with regional auriferous groundwater in the crust-crossing faults, causingboiling of the fluid mixture and depositing Te, Au, Pb in the process of mixing andboiling. The precipitates of Te, Au, and Pb 'reworked' and added Te, Au, Pb to theearier stages Au concentrates, forming rich ores of Au-Te association. Thismechwhsm is suPPorted by geological and geochemical characteristics of theDongping tyPe gold deposits, which range between tyPical epithermal gold depositsand the Dashuigou Te deposit of the mantle-degassing origin. Te is believed to comefrom the 'magma degassing' during regional mantle plutne process in the northwestHebei, China.
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