Historic Mineral Prospecting: A North American Perspective
by
Elizabeth Wilson
Fall 2002
GO 336 Mineralogy
Emporia State University
Introduction A Historic Timeline Present Prospecting Conclusion
(Click images for larger view)
Introduction
Long before the development of writing, humans recognized such distinct mineral properties
such as hardness, cohesiveness, and color (Rapp and Hill, 1998; 113). In fact, mineral prospecting
has been a part of human culture for thousands of years. Focusing on
North America alone, evidence has suggested man to have occupied this land for nearly 12,000
years. The archaeological record has yielded evidence to suggest man's use of chalcedony,
hematite, and other raw materials. Given this record, it is evident that people were selective
in their choice of mineral usage.
Minerals have always been valuable to mankind. From the Paleo-Indians to
modern man, we have prospected minerals for survival methods, aesthetic
purposes, and economic trade. Humans found that the
hardness and cohesiveness of quartz was valuable in toolmaking and the brilliant colors of
minerals, such as hematite, were useful in cave paintings. Following
a timeline, from a prehistoric age, we'll see how our North American ancestors have
utilized and prospected selected minerals.
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A Historic Timeline
15,000 Years Ago The Würm Glaciation
Theories center on the notion that during the Würm glaciation, approximately 15,000 years
ago, sea levels had receded such that a land bridge existed between Siberia and Alaska
(Stearns, 2001). By way of this land bridge, presumably North America was first colonized.
Some archaeologists suggest human occupation as far back as 40,000 years ago; however
radiocarbon dates prove human existence in North America at 12,000 years ago, upon which
ice sheets retreated due to a warming and moister climate. The warm climate created an
ice-free corridor in which our ancient ancestors would descend (Stearns, 2001).
Chert
Image taken from
Florida Museum of
Natural History
Chert is a general term used to define rock primarily composed of quartz.
In North America, chert projectile points have been discovered from this early period. They
exhibit sharp, conchoidal fracture, thus providing a good survival tool. Mammoths, mastodons, and other
large game animals provided the only subsistence for the early inhabitants as the climate
of the Würm glaciation was too harsh for plant subsistence. Thus, quartz was the first mineral of choice as an
adaptation to the environment and the beginnings of mineral prospecting.
12,000 Years Ago Paleo-Indians
Approximately 12,000 years ago, the first true inhabitants of North America arrived.
This is evidenced
in Clovis, New Mexico from which the term "Clovis" is derived to describe the projectile
points characteristic of this time period. The large game hunters and
gatherers are whom archaeologists
refer to as the Paleo-Indians. “The term Paleo-Indian refers to late Pleistocene Native
Americans, people ancestral to modern Native Americans but living at a time remote from our
own and in an environment unfamiliar to us today” (Cordell, 1997; 67). As glaciers receded,
these individuals appeared to become more nomadic, moving more frequently following
animal migrations. Artifacts discovered at various kill sites include Clovis projectile points
manufactured from chalcedony, obsidian, chert, and ivory. Such materials are significant such
that they are indicators of what and where these individuals were mineral prospecting for effective
survival tools. Chalcedony, shown below, makes up a large percentage of Clovis artifacts during the
Paleo-Indian period.
Chalcedony
Image taken from
Mineralogical Research Co.
The chalcedony projectile points have been sourced to Knife River chalcedony from North
Dakota. This location indicates the great distance our early ancestors had traveled since
their colonization of North America.
Chalcedony Clovis Projectile Point
Image taken from
Upper Midwest Rock Art
Research Association
Meanwhile, as the Paleo-Indians are hunting
mammoths, mastodons, and bison, the human population in North America is significantly
increasing. Crop agriculture has not yet been developed, thus hunting and gathering is the
primary source of subsistence. Gradually the sustaining environment for large game
animals is changing while they are increasingly hunted and killed. This transition
of population, subsistence, and environment emerges a new development of culture, which
we refer to as the Archaic period.
5500 B.C. Archaic People
The Archaic period dates at approximately 5500 BC and marks a stage of development from
the end of the Pleistocene to the development and adoption of agriculture (Cordell, 1997; 102).
Bison continue to thrive as they can maintain a population in the new, warmer environment, unlike
the other large game animals. Archaic peoples obtain cultivated crops from those that had
been domesticated far into Mesoamerica. Thus, there is an increased dependence on plant
foods, which lead to the making of additional tools. Beyond the usage of minerals for tool making as
described above, Archaic people prospected minerals for other purposes. Archaic burial sites
in North America reveal ornaments made of galena, a brilliant silvery mineral.
Galena
Image taken from
Dartmouth College
Galena has been reported from more than two hundred prehistoric Archaic sites in eastern
North America (Rapp and Hill, 1998; 120). Of these sites, galena recovered was associated with burials
in over half of the sites. Galena sources are numerous in places such as
the Appalachian region and northeastern Oklahoma.
2200 B.C. Late Archaic
Late Archaic, approximately 2200 BC, was characteristic of an increase and
stabilization of population and cultures as the climate was more moderate compared
to that of previous periods. It is evident that for nearly 12,000
years individuals have
undeniably made social and technological adaptations to a fluctuating climate of the
surrounding environment. Late Archaic indicates an increase use of minerals from distant sources, such as copper, hematite, and
selenite suggesting increased mineral prospecting and supporting the notion of a developing
culture.
Copper
Image taken from
Bisbee Mining and Historical Museum: Bisbee Mineral Hall
Copper artifacts first appear during the Late Archaic although some archaeologists
argue that copper mining began earlier and developed over time. Native copper was available in the form of nuggets outcropping at the surface in the
Great Lakes region (Rapp and Hill, 1998; 142). Given there was no technology available to chisel
large quantities, it is presumed Archaic societies would hammer pieces of copper to be used
for tools, ornaments, and decoration.
Selenite
Image taken from
Bob's Rock Shop
Selenite, a variety of gypsum, is a common mineral found in Mammoth Cave of Kentucky.
Late Archaic individuals are presumed to have traveled miles to collect selenite, which
was likely to be valued for their medicinal properties or ceremonial uses.
1000 B.C. End of Late Archaic to Historic Cultures
After the late Archaic, people continue to collect minerals for tool making, ceremonial
practices, cave paintings, and medicinal purposes. It is clear that mineral usage is widespread
throughout North America during our prehistory and carries over into historic periods. Hematite,
shown below, is a good example of this transition.
Hematite
Image taken from
History of Vesuvius Furnace
Hematite, a red iron oxide, first appears during the late Archaic.
Our early ancestors
discovery of the red powdered form is often associated with burial rituals and rock art.
Hematite Rock Art
Image taken from
Rock Art in Arkansas
In various rock shelters throughout Arkansas, hematite mineral pigments have been found.
Such evidence would suggest that native people would have ground the mineral for the manufacture
of paints used to color petroglyphs. As one travels to the American Southwest, hematite
pigments collected from local rock formations form the paint for red-on-buff AD 1150 Hohokam
pottery.
Hohokam Red-on-Buff Pottery
Image taken from
Ceramics: Deserts Farmers
at the River's Edge
Another prized mineral of the Southwest was turquoise.
Turquoise
Image taken from
The Celtic Connection and
http://www.wicca.com/
celtic/stones/images/turquoise.jpg
Turquoise is found extensively in Chaco Canyon during the 10th century. The source
area is not native to Chaco Canyon, thus the Ancestral Puebloan (Anasazi) were prospecting distances where
the mineral is found in the veins of weathered volcanic rocks. Heating and quenching the bedrock was used to free the turquoise to process the unique mineral into beads, ornaments, and jewelry for economic trade.
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Present Prospecting
Present prospecting technology has evolved tremendously since our Paleo-Indian ancestors, however
our reasons behind prospecting have remained fairly constant. Technological methods such as electronic sounding devices,
Global Positioning Systems (GPS), and Geographic Information Systems (GIS) have
revolutionized mineral prospecting, creating a greater supply for a higher demand of
essential minerals such as iron. Geophysical prospecting, such as magnetic susceptibility and
electromagnetic induction, the analysis of satellite imagery, aerial photographs, and
computer modeling with the application of GIS has been added to geophysical data to improve
the efficiency of present prospecting. Alternatively, like our ancient ancestors, modern prospecting also includes direct observation of geologic
structures and associated minerals, topographic features, and outcrops or stream channels.
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Conclusion
As stated previously, prospecting technology has evolved, however our reasons behind
prospecting have remained fairly constant. Minerals are used and needed in our daily activities
and for our well being. From the Paleo-Indians to our present prospectors, minerals
in North America have and will forever will be part in survival methods, aesthetic purposes, and economic trade.
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References
Cordell, L. 1997. Archaeology of the southwest. Academic Press, San Diego.
Rapp Jr. G.R. and C.L. Hill 1998. Geoarchaeology: The Earth-science approach to archaeological interpretation. Yale University Press, New Haven.
Stearns, P.N. 2001. Encyclopedia of World History: The first settlement of the Americas (15,000 years ago) http://aol.bartleby.com/67/28.html.
Retrieved on September 29, 2002.
Online Mineral References
Mineralogical Research Co., Chalcedony, http://www.minresco.com/special/spec3.htm. Retrieved on 19 November, 2002.
Upper Midwest Rock Art, Chalcedony Clovis Projectile Point, http://www.tcinternet.net/users/cbailey/lithic2.html. Retrieved on 19 November, 2002.
Florida Museum of Natural History, Chert, http://www.flmnh.ufl.edu/natsci/vertpaleo/aucilla/arpp60.htm. Retrieved on 19 November, 2002.
Bisbee Mining and Historical Museum: Bisbee Mineral Hall, Copper, http://www.bisbeemuseum.org/mineral_hall2.htm. Retrieved on 19 November, 2002.
Dartmouth College, Galena, http://www.dartmouth.edu/~rpsmith/Heavy_Metals.html. Retrieved on 19 November, 2002.
Lake Vesuvius, Hematite, http://www.fs.fed.us/r9/wayne/vesuvius_docs/vesuvius_furnace_history.html. Retrieved on 19 November, 2002.
Arkansas Archaeological Survey, Hematite Rock Art, http://rockart.uark.edu/. Retrieved on 19 November, 2002.
City of Phoenix, Hohokam Red-on-Buff Pottery, http://www.ci.phoenix.az.us/PUEBLO/dfceramc.html. Retrieved on 19 November, 2002.
Bob's Rock Shop, Selenite, http://www.rockhounds.com/rockshop/keller2.html. Retrieved on 19 November, 2002.
The Celtic Connection, Turquoise, http://www.wicca.com/celtic/stones/images/turquoise.jpg. Retrieved on 19 November, 2002.
***** All copyright images have been linked to their source and listed as a reference. *****
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This webpage was designed for GO336 Mineralogy
Instructor: Susie Aber of Emporia State University Earth Science Department.
For questions or comments contact Elizabeth Wilson. Created on October 17, 2002.
Copyright 2002 Elizabeth Wilson. All rights reserved.