What is the difference between XRF and XRD?
The two techniques are highly complementary materials analysis techniques, which when used together can can greatly improve accuracy of phase identification and quantification.
X-Ray Fluorescence (XRF) is used to identify and quantify (% or parts per million) elements, generally Fluorine (Z=9) to Uranium (Z=92), in a sample.
X-ray Diffraction (XRD) is the most accurate and direct method for identifying crystalline compounds (quartz- SiO2 , calcite- CaCO3, micas- KAl2(Si3Al)O10(OH,F)2, etc) and their concentration (%).
Are XRD and XRF destructive to my sample?
No. However to obtain accurate and representative results, both techniques generally require a powdered sample (pulverised to approx. 50 microns or less).
What materials can be tested?
Just about any type of solid material can be tested. Materials from naturally occuring sources i.e. soil, rock, clay, coal, etc through to industrial products such as residues, scale, cement, ceramic process materials etc. Just about anything you’re interested in.
How much sample is required for testing?
Amount of sample varies depending on technique used:
Approximately 1 gram is usually sufficient to identify and quantify crystalline minerals. When there is a limited amount of sample available we can generally mount milligram sized samples on a low background holder.
For clay analysis we generally ask for about 20-60 grams of sample depending on the clay percentage.
Major element analysis: approximately 0.4 to 5 grams of powdered sample
Trace element and semi-quantitative analyses: approximately 2 to 5 grams
Loss on Ignigtion (LOI): approximately 5 grams
1 to 20 grams depending on amount of particles and particle size.
Standard thin sections have dimensions of 75 x 26 mm. A sample larger than this would be ideal (generally fist sized).
Sample size should be kept to a minimum. Chip sized samples 15mm and less are ideal.
Material needs to be able to withstand the vaccum inside the SEM.
Samples may be mounted in resin to strengthen.Samples are also coated in an electrically conductive medium to prevent negatively charged electrons from building up on the sample during analysis.
How do I submit samples?
Prior to sending samples:
- Alert Sietronics Lab Services via email or phone that samples will be arriving
- Ensure a Purchase Order or Test Request form is enclosed detailing sample numbers and testing requirements.
- Ensure samples are labelled and appropriately sealed and packaged.
Samples can be sent to:
Attn: Lab Manager
Sietronics Pty Ltd
11 Cheney Place
Mitchell ACT 2911
P: (02) 6246 9299
How long do results take?
XRD: Generally 1-2 weeks from receipt of samples. 24-48 hour turn-around may be available upon request at additional cost.
XRF: Generally 2-3 weeks from receipt of sample
Particle Sizing: Generally 1-2 weeks
Petrology: Generally 4-6 weeks
SEM: Turn around time on application.