Ore genesis accumulation of hematite gravels called "pisolites" which form channel-iron deposits. These are preferred because they are cheap to mine. Lead-zinc deposits are generally accompanied by silver, hosted within the lead sulfide mineral galena or within the zinc sulfide mineral sphalerite. Lead and zinc deposits are formed by discharge of deep sedimentary brine onto the sea floor (termed "sedimentary exhalative" or SEDEX), or by replacement of limestone, in skarn deposits, some associated with submarine volcanoes (called volcanogenic massive sulfide ore deposits or VMS), or in the aureole of subvolcanic intrusions of granite. The vast majority of SEDEX lead and zinc deposits
The Galena Territory, Illinois The Galena Territory, Illinois The Galena Territory is a census-designated place in Jo Daviess County, Illinois, United States. Its population was 1,058 as of the 2010 census. The community consists of a private development located several miles southeast of downtown Galena. The Territory, which is managed by a homeowners association, has set aside of protected recreational land. The remainder is filled with low-density residential development and Eagle Ridge Resort & Spa. As of August 2017, there were 4,082 property owners, 554 permanent residences, and 1,675 vacation residences. The community includes an owners’ club, which houses recreational facilities for property owners