This rock was found in an area covered with approximately 200' of glacial till. The vein in the rock is partially oxidized. The rock is heavy; it shows some barely visible sparkle on its surface; the vesicles are all circular; and it is about 4" x 4". There is a bit of drozy (and also some lichen) in a few of the vesicles, and most of the pale green on its surface appears to be crystalized--perhaps it is olivine or remnants of fusion crust?? Any insights would be appreciated.
Location: found 3.5 miles south of the British Columbia border and 3 miles southwest of the northwest corner of Glacier National Park, Montana.
Surface rock: This was found on the surface, although it might have been dug up from approx. 1 foot below the surface from previous grading
Similarity to other rocks: I have lived at this local for 7 years and in this area for 20 years and I do not recall ever seeing something similar. The vesicles are unique and most hard rocks are rounded due to glacial wear. Most of the rocks I have seen in this area are glacier-worn rocks (like river rocks), mudstones, fractured limestone, some vulcanic/lava rock (15 miles south of this location).
Hardness: does not scratch with a coin but does with a knife = 5