rare earth elements in Wyoming

Wyo-DOG is a multi-tiered application using a
structured, relational database. Data is entered via
an application using the traditional client/server
(two-tier) model. Data in the relational database
can be queried directly by common modeling
applications such as ESRI’s ArcDesktop or via
custom, including Web-based, interfaces. Where
appropriate, data can also be made available to
other modeling applications through common
data exchange formats, such as CSV and XML, to
facilitate a variety of uses.
Wyo-DOG can be accessed from the WSGS website
at www.wsgs.uwyo.edu/. Wyo-DOG was initiated
with this project to fulfill the goal of creating
a statewide catalog of REE occurrences, as well as
occurrences of other resources. It is our hope that
adequate resources, including funding, personnel,
and time, will continue to be available to further
expand Wyo-DOG to include new data types,
investigations, and the many volumes of historical
data that reside in paper files at the WSGS.
samples and Analyses
This investigation is a survey of various sites across
Wyoming based on grab samples (i.e., small, unmeasured
samples, not necessarily representative of
a larger volume of material). Analyses of these grab
samples can neither confirm nor deny the presence
or absence of economic concentrations of REE
or other elements. A grab sample only represents
one small piece of evidence for the occurrence of a
mineral concentration or deposit. The grab sample
is not associated with, nor does it indicate a volume
of material greater than the size of the individual
sample. The elemental concentrations associated
with a grab sample may or may not extend into the
outcrop from which the sample was collected.
A thorough evaluation of a deposit, as opposed to
a survey of occurrences as presented in this report,
requires multiple samples be evaluated across
the range of geologic environments that occur at
a specific location. Each of those samples must
represent a specific volume of relatively uniform
material such that elemental concentrations can be
converted to tonnage estimates across the deposit.
Only then can the economic tenor of the deposit
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be estimated. No single sample can define or eliminate
the possibility of an economic deposit.
Not all samples are equal. The analysis of a panned
concentrate from a placer sample is not equivalent
to that of a grab sample. A panned concentrate results
from washing disaggregated grains in the field
with water to separate out the heavy ones from
lighter ones. Analytical results may show relatively
high values for some elements in the concentrate.
However, to provide proper perspective, a panned
concentrate analysis must be diluted to represent
the original larger volume of material from which
the concentrate was derived. This dilution may
reduce reported values by a factor of 10 to 100 or
more, depending on techniques and equipment
used in sampling. Placer samples are appropriately
described in both the text of this report and in
Wyo-DOG.
All sample analyses collected for this project were
completed by ALS Chemex of Reno, Nevada.
Analytical methods for historical samples included
within Wyo-DOG or this report are referred to
as generic if either the laboratory or the method
of analysis is not known. Geochemical analyses
on samples included whole rock analyses (major
element concentrations in the form of oxides) by
inductively coupled plasma (ICP), atomic emission
spectrometry or mass spectrometry, and atomic
adsorption. These methods, when preceded by effective
preparation techniques, can generally detect
most elements present in a sample from very low
concentrations in the range of less than 0.1 to 5
parts per million (ppm) up to ore-grade concentrations.
To put this in perspective, 1.0 percent is
equal to 10,000 ppm.
rare Earth Elements defined
Rare earth elements (a.k.a. rare earth metals) are
a group of metallic elements with similar physical
and chemical properties. Fifteen of these are
listed in the periodic table (table 1) in a series
from atomic numbers 57 through 71 known as the
lanthanide series. However, one highly-unstable
element, promethium, does not occur naturally on
earth, has a half-life of 17.7 years, and decays into