Mineralogical Characterization (via integrated analytical methods)


The Instrumentation Laboratory (LUIL) is equipped to analyze the composition and structure of a wide range of geological samples. Complementary techniques include optical microscope petrography, x-ray diffraction, scanning electron microscopy, inductively coupled plasma, fire assay and Fourier transform infrared spectroscopy.
 
LUCAS provides a variety of analytical techniques, so choosing the service that will provide the type of data you are looking for may be daunting. This chart is designed to help you decide what services would be suit the needs of your geological samples.
 
A Brief Comparison of Common Analytical Techniques For Geology 
 
Optical Microscope/ Petrography
 XRD (X-Ray Diffraction)
SEM (Scanning Electron Microscope) with Energy Dispersive X-ray Spectrometry
ICP Inductively Coupled Plasma - MS  or AES (Atomic Emission Spectrometry)
Fire Assay
FTIR Fourier Transform Infrared spectrometer
Reason for use:
Phase analysis, textural analysis
Phase analysis
High resolution imagery; Elemental concentrations and mineralogy of a user defined point (EDX)
Elemental concentrations of a bulk sample
Elemental concentrations of precious metals (Au, Ag)
Infrared analysis is used primarily for the identification of chemical functional groups in a compound or simple mixtures of compounds.
 Preparation:
Thin sections cut from a slab of rock
Powdered sample (as small as 2-4g)
Polished thin sections or SEM discs cut from a slab of rock
Powdered sample dissolved in acid (as small as 2-4g) with digestion method appropriate to desired results
30g - 50g representative crushed sample
Powdered sample (usually < 50 mg needed) or unmounted thin section
 Cost:
Moderate to high; need to pay for a trained individual to look at your sample
 Low
Variable; depends on level of detail desired and complexity of sample
Low to moderate, depending on number of elements that require quantification
Low to moderate, depending on number of samples and detection limit
Very low
 Speed:
Moderate to slow
Fast
Variable; depends on level of detail desired and complexity of sample
Fast to moderate
Fast
Fast
 Accuracy:
Qualitative to semi-quantiative; will positively ID minerals and phase percentages can be estimated; based on the skill of the petrographer
Semi-quantitative; will positively id minerals and phase percentages are estimated to about +/- 5%
Qualitative to quantitative depending on purpose for use; use of proper standardization techniques increases accuracy and time spent
Semi-quantitative to quantitative
Quantitative
Primarily a qualitative analytical technique
 Ideal for:
Most rock types, preferably unaltered with larger grain size
All rock types, including alteration minerals, zeolites, air sensitive samples
Most rock types, especially for determining zoning in minerals, elemental concentrations in a mineral and how it changes through a sample
Any rock type for major, trace and/or REE elements
Any rock thought to  contain gold, silver or other precious metals
Quick analysis of rocks and minerals for the presence or absence of functionalities associated with certain rock types. Eg clays, talc, carbonates, etc have characteristic infrared signatures
 
Have questions about this service?
Not sure if this test will help you?
Ready to submit your sample?
 
For more information, please contact:
Dr. Andrew Conly, Director, LUMINX
Phone: 807-343-8643
 
 

LUCAS Lakehead University