Coupard shrugged at the suggestion of danger.
Again, to go about eating this sample or inhaling the dust would be unwise as a matter of general principle, but beyond that, I am confident this is completely safe. And as to what we expect to see, well my dear friend, this is SCIENCE! To discard one's expectations and go with whatever is revealed through experiment and analysis is the adventure of it after all.
Glowing, or phosphorescence, can have several origins. Radioactivity generally speaking is not capable of engendering such an effect visible to the naked eye in daylight, at least for naturally occurring samples, as the requisite energy would be long spent before the rock was dug from the ground by prying hands.
A chemical reaction - remember, radioactivity is atomic, not chemical in origin - could be a culprit as well. If the sample was exposed to the atmosphere recently, a reaction with the oxygen or other chemical in the air could have such an effect as well.
And another possibility is bio-luminescence of some sort. Bio-luminescence is a very common phenomenon in the ocean for instance, as one only needs to disturb the water near the beach at night to see the glow of micro-organisms suspended in the water. In fact, during the recent war with Germany, the glow of those same micro-organisms would on occasion illuminate u-boats to the relief of anxious merchantmen and their naval escorts!
But as for our sample here... let me think on the specifics for awhile and I will inform you of my conclusions.
Coupard then turned to Livingston and addressed her inquiry regarding the origin
That question is a matter of probability, not certainty. Near the coast, the sediment is dominated by alluvial deposits - soil or rocks left behind fairly recently by rivers and tidal action. This in fact continues as far inland as Columbia, with the age of the strata increasing with distance from the ocean. Further inland than that, the geology is dominated by a variety of rocks of far older origin, be they igneous deposits circa the Cambrian - before the dinosaurs - or various metamorphic deposits. This rock is new to me, so it is obscure no matter its origin, but odder things have happened than a strange sample showing up in our very backyard. Again, let me ponder the question, and I will have a clearer answer for you in a short time.