Say 'Ahh' on Mars. This image from NASA's Curiosity rover shows the open inlet where powered rock and soil samples will be funneled down for analysis. CheMin (short for Chemistry and Mineralogy) will identify the minerals in samples of powdered rock or soil.
Dr. David Blake (principal investigator of the CheMin) gives a nice overview of CheMin in this video:
How do we interpret the data?
X-ray pass through the material which causes them to diffract in circular patterns which are captured with an image sensor. These patterns appear as rings which can be analyzed for mineral and elemental composition. The colors in the graphic below represent the intensity of the X-rays, with red being the most intense.
How do we analyze these patterns?
Segment from a full demonstration by Dr. David Blake (see below) where he explains how we analyze data from CheMin: