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The mineralogical and geochemical peculiarities of alunite secondary quartzites of Aksakata deposit were studied. Alunites develop on the contact of andesite porphyries of Akcha series (Middle Carbon) and subvolcanic body of diorite and andesite porphyries of the same age. In the north part the zone of secondary quartzites is covered by sedimentary-volcanic rocks (Lower Permian). Alunites were formed regular regular bedding sheetlike bodies, thickness of which is varies from 100 up to 150 m. Their dipis to north-west under deposits of Lower Permian. In latitudinal direction they are traced up to 2 km. Horizontal zonality of location of secondary quartzites facies was studied. From center to margin parts there are observed the following zones: monoquartzites- alunites- pyrophyllites - sericites. In the secondary quartzites of Aksakata deposit the complex of minerals was revealed: native gold, cinnabar, galena, sphalerite, pyrite, tetrahedrite, magnetite, hematite, hydrogoethite, diaspore, corund, fluor spar, calcite, ankerite, barite, jarosite alunite, pyrophyllite, sericite, chlorite, kaoline, halloysite, etc. In the west part of deposit in brecciated zone of monoquartzites cinnabar mineralization is located, which traced along the strike up to 500 m. In sericitic and monoquartzite facies pyrite is formed abundant impregnation. Gold and silver concentrations in pyrite are: 2-40 g/t and 4-2100 g/t correspondingly. In paragenesis of native gold there are the follow minerals: cinnabar, galena, sphalerite, pyrite, tetrahedrite.
Alunite secondary quartzites formation (after N.I.Nakovnik, S.I.Naboko) took place as a result of solfatare fluids activity during the final stages of volcanic process. Mineralization of cinnabar, native gold, sulfides and sulfosalts were results of hydrothermal process, which was manifested after secondary quartzites formation. This ore mineralization is formed the cement of breccia in monoquartzite facies. Gold mineralization in alunite facies of the secondary quartzites recently attracts the attention of researchers (M.M.Konstantinov, 2007). Non-traditional gold deposits of alunite-quartzite type are successfully mining in Peru, Chile, Taiwan, Russia. This type of deposits is perspective also for Uzbekistan, where manifestations of secondary quartzites are known. Thus, in the Chatkal Ridge there are known a number manifestations of the secondary quartzites: Akcha, Shavaz, Altyn-Bel, Karankul, etc. In the Kurama Ridge series of the secondary quartzites occur (Gushsay, Gavasay, etc).
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