As you guys say, you can't judge a book by its cover, or a rock by its color. To even speculate based on pan cam "spectra" is weak science at best. It was curious that they omitted any comparison of Bounce with the rocks of Eagle crater. Curious in omission. I thought bounce looked much like the rocks of the crater, including the curious (usually curved) voids. I went back and looked at Mossbauer spectra from there, and see little difference to Bounce except for the "magnetic phases" peaks. These could be accounted for by the presence of spheres at the crater only. The Mossbauer seems like a somewhat unreliable instrument to me that you have to cook up model mixtures to explain the spectra. Slight peak assymetries lead to the inclusion of additional components. You could cook up just about any spectra with enough ingredients. Only the a/x ray spectrometer seems to provide trustworthy data - and that in elemental composition only, not mineralogy. I wish they would have shown the actual elemental amounts for Bounce and Guadalupe, instead of just this bulls-eye plot, but I guess I'll take their word for it.

Syenite is a very light colored intrusive rock - though I don't know what the extrusive equivalent is.