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
Galena, Ohio Galena, Ohio Galena is a village in Delaware County, Ohio, United States. The population was 653 at the 2010 census. Galena was originally called Zoar, and under the latter name was platted in 1816. A post office called Galena has been in operation since 1834. Galena is located at (40.215214, -82.881757). According to the United States Census Bureau, the village has a total area of , of which is land and is water. As of the census of 2010, there were 653 people, 214 households, and 172 families residing in the village. The population density was . There were 237