Resources & Articles

Two Powerful Techniques – Two Completely Different Questions

XRF and XRD are often mentioned together because both use X-rays. However, they are designed to answer completely different questions.

Here’s a practical comparison.

A Practical Example

Imagine two steel samples.

Both contain:

• 70% Iron
• 20% Chromium
• 10% Nickel

An XRF analyzer will report almost identical chemical compositions.

However…

One sample may be Austenitic Stainless Steel, while the other has transformed into Martensitic Stainless Steel after heat treatment.

The chemistry is nearly identical.

The crystal structure is completely different.

Only XRD can clearly distinguish between these phases.

Precious Metals Example

For precious metal recycling:

An XRF analyzer can quickly determine that a catalyst contains platinum, palladium and rhodium, or that a gold alloy contains 75% Au.

But if you need to know:

• Which oxide phases are present,
• Whether platinum exists as metallic Pt or PtO₂,
• What crystalline compounds formed during processing,

then XRD becomes the appropriate tool.

Which One Should You Choose?

Choose XRF if you need to know:

• What elements are present
• Their concentrations
• Fast quality control
• Alloy identification
• Scrap sorting
• Precious metals analysis

Choose XRD if you need to know:

• Crystal structure
• Phase identification
• Heat treatment effects
• Mineralogy
• Material research and development

Final Thought

A simple way to remember the difference:

XRF tells you WHAT the material is made of.

XRD tells you HOW the material is built.

They are not competing technologies—they are complementary tools. In many advanced laboratories, both are used together to obtain a complete understanding of a material.