GRD00B6S0
I-430
Foid-Bearing Extrusive
Cenozoic › Paleogene › Eocene › Early Eocene › Ypresian
48.6
-
55.8
0
Ritter 154 › Cabinet 16 › Drawer N
-
Pseudo-leucite phonolite. Emplaced between 54 to 50 Ma.
GSA Bull 52: 1733 (1941)
Highwood Mtns
Montana
Highwood Mtn
Latitude: 47.46°
Longitude: -110.56°