What do I need to know (or tell Ken) before my session in order to calibrate for WDS?

Calibration Planning

  • If you are going to calibrate yourself, the following list contains some questions that you'll need to answer in order to do it.
  • If you would like us to calibrate for you, and it is a new calibration1, we also need this information. Please contact Ken Domanik before your scheduled probe session (an email the day before your probe day is best) and provide as much of the following information as you can. If we need additional information or clarification we'll contact you. The more of this information you can provide in advance, the faster we can get you going collecting your data.

Data needed for calibration:

  1. What elements you plan to analyze for and what type of minerals or materials these elements are contained in (e.g. anhydrous silicate minerals, hydrous silicate glasses, chrome alloy steels, etc.)?2
  2. What is the general composition (roughly) of these matrix minerals or materials.3 (This information is needed primarily to determine if peak or background interferences may be present).
  3. Are the minerals or materials of interest small (< 6 μm) in size.
  4. Are any of the elements you plan to analyze of more importance than the others (e.g. as in geothermobarometry) or do you need to know their concentrations accurately at trace levels (< 0.1 wt%)?
  5. What are you trying to determine (e.g. general composition of all phases present, trace Ni partitioning between metal and olivine, age dating of monazite, Sb content of archaeological artifacts, etc.)?

1If you have run the same type of analyses on our microprobe before, specifying "same calibration as last time" or something to that effect is usually sufficient.
2Some types of analyses are so common, particularly for geological and meteorite samples, that we can guess what elements you need and make any necessary adjustments during your probe session. For example, general analysis of all major silicate minerals in a rock section (standard silicate analysis), general analysis of all major metals and sulfides in a chondritic meteorite (standard metals and sulfides), etc. In cases like these a brief specification (e.g. standard silicates) is generally enough.
3In some cases, especially for a completely unknown sample, it may be necessary to actually get the sample on the microprobe in order to answer the above questions. However a good guess prior to starting is usually better than nothing.