THE HIENDELAENCINA MINING DISTRICT (GUADALAJARA, SPAIN)

The Hiendelaencina mining district (Guadalajara, Spain), includes the ore deposits of the Hiendelaencina, La Bodera and Congostrina areas. In this paper a general overview of this district is given, with special emphasis on the parageneses. mineralizing stages and chemical characteristics of the sulphides and sulphosalts. These deposits contain silver in Sb-rich sulphosalts such as freibergite, pyrargyrite, polybasite, stephanite, freieslebenite and the Bi-rich sulphosalt, aramayoite. Three mineralizing stages have been detected in Hiendelaencina and Congostrina: (1) As-Fe; (2) Cu-Zn-Fe-Sb-Ag; and (3) Pb-Sb-Ag (+/- Bi) but only two in La Bodera (stages 2 and 3). The average sulphosalt formulas are: freibergite (Cu0.5 Ag5.9) (Fe1.42 Zn0.66) (Sb4.49 As0.02) S13; pyrargyrite Ag3.38 Sb1.0 S3; polybasite (Ag16.3CuO.15) (Sb2.8 As0.15)S11; stephanite Ag6.7 Sb1.38 S4; freieslebenite Ag1.1 Sb0.83 Pb1.05 S3 and aramayoite Ag1.06 Bi0.35 Sb0.7 Pb0.03 S2. The compositional patterns of these sulphosalts (mainly based on the Sb/(Sb+Ag), Ag/(Ag+Cu), Sb(Ag+As) and Ag/(Ag+Cu) ratios) are outlined, pointing broadly to similar tendencies in their chemistry and genetic conditions.