Electron microprobe beam scans across part of a zeolite crystal from about 50 m in drill hole Y-13. Yellowstone National Park, Wyoming. No date.

Photo caption: Y-13 analcime-wairakite. Figure caption: Electron microprobe beam scans across part of a zeolite crystal from about 50 m in drill hole Y-13. In both photographs, the center of the crystal is at left, and part of the outer rim is near the upper right-hand corner of the scan. Scale bar is 14 microns. Distribution of sodium. Crystal is sodium-rich analcime near the center and at the rim (brightest areas). Innermost part contains abundant potassium (coincident with the dark oblong part). No index card. Published as Figure 16-A in Zeolites in Yellowstone National Park. The Mineralogical Record; 12: 29-38.