Analytical Services

New prices since 06/2018! We are your partner for fast and reliable analytical work of mineral phases and compounds! 

With our unique combination and comprehensive analytical methods (P-XRD, SC-XRD, SEM-EDS and Raman spectroscopy) we are the leader for analytical identification of mineralogical samples and compounds within Germany. It is important to us that you will have a definite determination of your samples. Therefore we are specialists for several methods that we combine to identify unknown mineral phases. If your sample should be an unknown phase to date, a complete structural solution might be the next step till the mineral will be accepted as a new species. We will help you in this process with all our experience. 

If you should have another request and you think we might be the best partner for, don´t hesitate to write us an e-mail via our contact form. We offer a wide range of x-ray, spectroscopic techniques for crystalline matter and also methods for element quantification.

Guidelines for the choice of an analytical method for phase ID: 

 

Chemical analysis of a sample (EDS Analysis)

The energy dispersive xray analysis carried out with a SEM gives information about the chemical compounds within the sample. The data is semi-quantitative and made under variable pressure to avoid carbon coating of non conductive, non-flat samples. 

cd1

  remlabor  cd5

 recommended, if:

 not recommended, if:

  • very small sample amounts (µg regime)
  • sample are likely to consist only out of very light elements (< carbon) 
  • ore-microscopic studies with inhomogenity (cut and polished section is necessary before!)
  • differentiation between complex silicates or mineral phases where too many chemical related phases exist (eg. Tl-sulfides, sulfosalts). SEM-EDS is a semi-quantitative method, that are less precise than EPMA-WDS results. 
  • studies of morphology; sometimes morphology gives a hint on the underlying symmetry and allows assigment to a crystal system
  • Polished sections with phase discrimination in µm-area, sulfides: better EPMA-WDS
  • absolute quantitative results of flat polished section measured against standards (EPMA-WDS)

Raman Spectroscopy on mineralogical samples (Raman Spectroscopy)

Raman spectroscopy allows the identification of small amounts of unknown crystalline solids by                                          inelastic scattering of light due to vibrational transitions within the molecules scale. When there is a Raman transition of a molecule group within the crystal, the light is emitted at a different wavelength compared to the incident light wavelength and we observe a peak in the spectrum at a certain value on the x-axis (Raman-Shift). In consequence a complex spectrum with many transitions is obtained for a certain crystal structure which is then compared against the database. Even if the Raman spectrum is not always as helpful as powder data it allows to obtain data from an extremely small sample amount without destruction.

quartz  nr3 550px raman3a

 recommended, if:

 not recommended, if:

  • very small sample amounts (mg-µg regime)
  • common minerals shall be identified, as not all are have a reference up to now
  • if fluorescence superimposes with the Raman spectrum very strong. 
  • sensitive for modification distinction, like XRD Raman spectra are a result of the structural character of the crystal, eg. local symmetry
  • sulfides, metals 
  • rare phases with missing references data, or some rare minerals published 10 years or more before. 
  • no isolation from the crystal out of the matrix, insitu measurement
  • if crystallinity is bad

XRD - Xray Powder Diffraction (P-XRD)

Powder diffraction of a sample (P-XRD) allows the identification of crystalline phases by observing the diffraction conditions of the crystal structure at a specific x-ray wavenlenght (CuKalpha). The sample becomes crushed and powdered to obtain diffraction condition for all crystallite orientations at different 2Theta angles. Apart from qualitatitive phase ID, we offer Rietveld refinement for the determination of the phase volume or refinement of a crystal structure. The minimum amount is around a few mg. With the standard configuration the FWHM is ~0.15° 2Theta. 

P1010028  asd2theta

 recommended, if:

 not recommended, if:

  • as a combination of chemical information and structural data is often needed for reliable phase ID
  • very small sample amounts (µg regime): choose SXRD/Raman spectroscopy!
  • sample should not be destroyed
 
  • sensitive for spatial changes in the crystal structure due to atomic substitution, phase transition
  • structure is known, but chemical composition is needed for further classification (often within a specific mineral group, eg. vivianite group)
  • chemical information is not suitable or sufficient for phase ID
  • ore microscopic examination with trace amounts, eg. rare phases with only a phase volume percentage of less than 1%

SXRD - Single Crystal Diffraction (S-XRD)

Single crystal diffractomety, a standard for structure solution and refinement, allows a fast determination of the lattice parameters and space group of single crystals. It is of importance when there is not enough sample amount for Bragg Brentano diffraction experiments (PXRD). A small amount of polycrystalline material can be then mounted on the capillary and high intensity data without favoured orientation can be obtained while resolution is sacrificed (~0.4° 2Theta resolution in a standard experiment). 

recommended, if:

not recommended, if:

  • small amounts, or unique samples that should not be sacrificed
  • if powder diffraction is needed and enough material is available for diffraction in Bragg Brentano geometry (PXRD) 
 
  • lattice parameters / space group determination
  • if the mineral group is already known and chemical information is needed to identify a mineral endmember.
 
  • ore-microscopic mineralogy, inclusions and extremely tiny samples below 50µm 

 

 


Photography service of minerals  (Macrophotography- Stacking)

We also offer a wide range of methods to photograph small regions of interest.

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