Illustrated Glossary of Local Mine Related Terms
- Adit: The entrance to horizontal tunnels driven into a hill side
to gain access to the mineral deposits is termed an adit.
- Blackjack is a very dark almost black variety of the mineral
sphalerite (ZnS).
- Bone refers to a gray brown rather porous variety of the mineral
smithsonite (ZnCO3) it is synonymous with drybone.
- Cave: When most of us see the term cave we think of something
like Crystal Lake Cave or Mammoth Cave but to the miners a cave was a
segment of of crevice which was generally wider than typical and generally
contained ore minerals. Many times the cave was an open space and did have
the appearance of the common 'cave' but more frequently when they first
encountered such it would have been filled entirely with red clay and ore
minerals. At notable example would have been Stewart's Cave.
- Cog Ore refers to the cubs or cubic masses of the mineral galena
that was found generally in the soil; this was the primary target of the
earliest mining operations.
- Crevice: In the area around Dubuque the Galena Dolomite is broken
or cut by a series of generally trending east-west fractures or crevices.
These extend the fill thickness of the layer. The ore minerals were
deposited along these.
- Diggings refers to a group of closely spaced surface mines. These
were usually nothing more that pits and trenches and generally represent
the earliest form or mining.
- Drybone refers to a gray brown rather porous variety of the
mineral smithsonite (ZnCO3); it is synonymous with bone.
- Heavy Spar is the local term for the mineral barite (BaSO4)
which resembles coarsely crystalline variety of the mineral calcite (CaCO3)
but is much heavier.
- Jack is a general term for any variety of the mineral sphalerite
(ZnS)
- Load or Lead (pronounced like 'read' and not like the
element (Pb)) was a particularly rich occurrence of ore minerals along a
crevice. It would appear that sometimes this name was applied with a whole
lot of wishful thinking.
- Mine: A mine would have been any sort of operation where there
was an attempt to find and obtain lead or zinc minerals from the soil or
rock. Sometimes the name of a mine endured for most of the mining era
while other names were ephemeral or even just on paper.
- Mineral Hole was small shallow conical pit dug into the soil in
search of mineral, generally cog ore. In the literature of mining in other
parts of the United States these would have been called glory holes
or prospect pits.
- Opening: A crevice for the most part was only an inch or two wide
but at particular stratigraphic horizons the width was much greater, these
wider horizons were called openings. In the case of the Level Crevice
there were three openings that were actively mined.
- Range: Sulfide minerals were not found everywhere in the Dubuque
area but instead in more localized areas called ranges. Pikes Peak Range
was the most familiar range and probably the most productive.
- Shaft: A shaft is a vertical entrance driven down from the
surface to the mine, cave, or crevice. These were anywhere from 15 feet
deep to 200 plus feet deep. Generally they were about five feet by five
feet in cross section.
View
looking up a shaft into Ewing Diggings.
- Spar refers to the coarsely crystalline variety of the
mineral calcite (CaCO3).
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