This image from the rover Curiosity is a high-resolution black-and-white from the ChemCam remote micro-imager and a color image provided by the Mastcam. The image show a rock “shell” (not drilled) with laser targets shown as colored circles and below is the chemical composition produced from the laser (spectrographic) examination. The feature is called “Winnipesaukee”.
The laser did the examination from three meters away which is pretty amazing. How was the structure formed? The answer to that question is difficult to answer, but there are some theories.
Check out the results from the spectrographic exam and the theories how such a feature could occur.